Experiment #2: (Drunken) Brownies

I got a request from my friend J.K. (a closeted sweet addict) to make brownies and I knew just the recipe that I wanted to try (from my new Tartine Bakery book of course). And so last night after dinner and lots of wine, my chocolate craving surged through me. Drunken and determined, I undertook a last-minute task to bake chocolate brownies. Thank goodness that this recipe was pretty straight-forward and I actually had everything on hand. Sorry, there was no real “pre-lab” or “experimental procedure” preparations on my part; I just starting baking. What happens when a drunken girl bakes? A mess happens.

Brownies (adapted from Tartine)

Ingredients

1 ½ sticks of butter

1 pound of chocolate (Elizabeth calls for bittersweet, but I used semi-sweet chocolate chips, which worked fine)

5 large eggs

2 cups of light brown sugar

¾ cup + 2 Tbs of flour

¼ tsp of salt

1 tsp of vanilla

Nuts (I used pistachios)

1. Pre-heat oven to 350oC.

2. Melt the butter in a medium saucepan. Once melted, turn off the heat and add the chocolate and stir until completely melted. Set aside to cool.

3. In a mixing bowl, add the eggs, brown sugar, and salt. Using the whisk attachment, beat at highest speed until the mixture thickens. (4-5 minutes).

4. Sift the flour into the egg-sugar mixture and use a rubber spatula to incorporate fully.

5. Add the cooled chocolate to the bowl, mixing from bottom to top to incorporate the chocolate (the chocolate tends to sink to the bottom).

6. Pour the batter into a 13 x 9 pan and bake for ~40 minutes. (You can’t do a toothpick test to check the doneness of the brownies; there’s just too much darn chocolate. If the top looks a bit crusty, then you’re done!). Cool before eating.

Results and Discussion and Conclusion

Having already consumed a large portion of the delicious brownies, I’m amazed how well they turned out, despite having made them in a drunken state. I think that says a lot about how easy the recipe is and that anything with lots of butter + sugar + chocolate is bound to be delicious. But I really think that the light-and-tenderly soft texture is attributed to beating the eggs and incorporating air into them. Upon reflection, I’m not sure if I deflated the batter with my drunken mixing, so perhaps the brownies could have been even more light and fluffy. Nevertheless, let it be known that this recipe yields a most deliciously moist-and-light, tender-and-soft, and chocolatety-delightful brownie.

Experiment #1: Results and Discussion/Conclusion

There were a lot of steps involved with making this entire cake and I’ve learned a lot from this experiment. Here’s the play-by-play breakdown on each step:

Part 1: Making the génoise cake
Not to intimate anyone into making this cake, but even the fist task of lining the pan with parchment paper is not as easy as it seems in the instructions; it actually required some math! First I traced the bottom of the pan on the parchment paper (pencil works well) and cutting out the piece to fit the bottom. For the sides, cut a 2-3” wide strip (the cake doesn’t rise all the way to the top so it doesn’t have to be perfect) of parchment and as long as the circumference of the pan. How long is that? Well, 2πr long. Or 2*3.14 * the radius of your pan (5” for my 10” diameter pan). So I cut a piece that was 31” long. Is this lesson in geometry a bit excessive for a stupid pan lining? Yeah, but at least you won’t waste your parchment paper. :P I found that it was easiest to line the sides first with parchment paper, then slide in the bottom piece so that it “holds” the sides in.

The prep work for the cake wasn’t too hard at first; after all, I’ve made cake batters before. But then I tried the folding of the flour into the batter and lo-and-behold, the flour sinking to the bottom, just as Elizabeth had warned. I thought I had my eye on the flour, but as I was pouring out the batter, I found a significant amount of flour at the bottom so I had to quickly blend in the flour at the last minute. The result: lumps in my batter. I definitely need some work practicing folding in flour for this cake before I can call up Tartine for a try-out.

Part 2: Making the pastry cream
I discovered a trick early on in the process of making the pastry cream. My vanilla beans were very stiff and I could not slice it in half without cracking the whole thing. I first contemplated adding the hard chunks of vanilla bean, pod and all, into the milk, but came up with a better idea: microwave it! Twenty seconds and the bean was soft and sliceable again. The most challenging part was the addition of the hot milk to the egg/sugar mixture while whisking; this required the ability to do two different actions with your hands (kind of like patting your head with one hand and rubbing your belly with the other). I ended up whisking with my left hand and pouring with my right hand, which was probably not the best way to do it since I am right-handed. Next time, I will set up the egg/sugar bowl to the right of my burners, so that I can pour the hot milk from the left and whisk with my dominant right hand. I also found that the cream didn’t flow very quickly through the sieve. At all. So I used my spoon to smoosh it through. Not elegant, but it works.

In the end, the pastry cream ended up much thicker than I imagined; it was the consistency of a thick pudding after it cooled (I could make plenty of polymer references to describe the consistency, but there’s definitely no comparison in taste!). I stirred it occasionally while I got ready to assemble the cake.

Part 3: Making the filling and assembling the cake
Elizabeth instructs us to line just the inside rim of the pan with plastic wrap and not the bottom. When I read this, I was puzzled on how to achieve this. So with a little experimentation, I found this way worked for me: take two large sheets of plastic wrap and stick them together along the long side. Then put the bottom of the pan on top of the wrap, and wrap the plastic wrap into the middle of the pan. Then I placed the outside rim of the pan around the plastic wrapped bottom. Once the rim of the pan is attached, unfold the plastic wrap and pull it back so that it covers the sides and hangs over the rim of the pan. Voila!

To cut the cake evenly, I found myself placing my hand on top to gauge the evenness of the cut. I also stooped down to counter-level so that I could see the cutting process. I sawed gently all the way around first to mark where I would cut, then I cut deeper the second time around. That worked pretty well and cake came out fairly even!

In my preparation to make the filling, I was intrigued about the role of gelatin; I had never used it in my baking before. What was this stuff going to do to the pastry cream that I had just made? I was amazed that the stuff absorbed all of the water I added almost immediately to form what we would call in lab a “gel.” I wondered how adding this gelly-blob to the pastry cream would work, and I was amazed that when whisked into the hot pastry cream, it “melted” to form a smooth cream product. (At my job, we don’t want our gels to melt like that!) Honestly, the cream looked the same before and after the gelatin. But I think if I were to compare cooled plain pastry cream and pastry cream with gelatin, I would notice that the one with gelatin was more firm since macromolecules such as gelatin will have different physical properties at lower temperatures. I’m imagining the protein structure of gelatin freezing up when it is cooled, trapping the pastry cream in its network. The result is a sliceable cream filling.

When I took the cake out of the fridge to top it with the whipped cream, the assembled cake reminded me much of a giant ice cream sandwich. The filling peaking out on sides of the cake wasn’t perfectly smooth and I realize now that I should have put more pressure to even out the filling when I originally assembled the cake. Oh well, I’ll have to improvise. Since I didn’t have any more strawberries left, I sliced some nectarines thinly and lined them along the side of the cake. The cake didn’t look like the one in the book, but it still looked good to eat!

I added the whip cream topping next and being the perfectionist that I am, I kept smoothing the top, and eventually it started to look “grainy.” Adding more whipped cream didn’t help either; I think there is a certain window of time that one can manipulate the whip cream before the “graininess” sets in. Lesson learned; plop the whipped topping down, smooth over once or twice then leave it alone.
Perfect!

Too much manipulation of whip cream :(

Conclusion

This by no means is an easy cake to make, but with a little determination and a big sweet tooth, it can be done in about 2.5-3 hours. Overall, the taste of my cake was successful (though I’ve never tasted the real thing); it was creamy, not too sweet and the cake base was scrumptious (so my friend C.H. said!) The co-workers devoured it and I’ve probably gained a pound or two from it, but it was well worth the experience. In future repeats of this experiment, I hope to address the key mistakes I made, which will hopefully improve the aesthetic quality of the cake:

*Genoise cake: when adding the flour to the batter, REALLY dig to the bottom of the bowl to scoop up the flour and to ensure good mixing.

*Pastry cream: work with the egg/sugar mixture on the right-hand side (if you’re right-handed like me); pour milk with the left hand, whisk with the right.

*Cake assembly: I would probably put more syrup on the cut-side of the top of the cake so that it would have been a bit sweeter. Also, press the top of the cake firmly to make sure filling will be smooth on the sides of the cake and don’t mess around with the whip cream topping too much or it’ll look ugly. Still tastes good though!

Experiment #1: Experimental Procedure

The key part in designing this experimental procedure is timing; I need to plan out how long each component will take so that I can still have time to do other things. Of course, I’m going to need to make the cake base and the pastry cream first, and since the cake needs to be completely cooked before I cut it, I’ll make that one first. The pastry cream can still be warm because I need to warm it up in the making of the filling anyway.

I’ve also made a few procedural edits to make things easier for me (like preparing the egg mix before concentration on the making the milk mixture in the pastry cream, which can be easy to burn). I used to adjust the procedures for my chemistry labs too so that things would go more smoothly for me in the experiment (and many times, safer too). Also, I recommend reading though the results/discussion section to get some tips on what I did during the experiment to make it work (and the lessons I learned from things that didn’t work!)

Total time: ~2 ½ - 3 hrs. (including cooling time)

(Adapted from Tartine by Elizabeth Prueitt and Chad Robertson)
Part 1: Génoise Cake Base
The recipe given below makes one 10” cake, which will be split into two to assemble the entire cake.
Ingredients
5 Tbsp of unsalted butter
1 1/3 cup of all-purpose flour
1 Tbsp of cornstarch
6 large eggs
A pinch of salt
1 cup + 1 Tbsp of sugar

1. Preheat oven to 350oC and line a 10” x 3” springform pan (bottom x side) with parchment paper.

2. Melt the butter in a small saucepan. Set aside and keep warm.

3. Sift together the flour and cornstarch and set aside.

4. Get a saucepan that is big enough to fit the mixing bowl of your stand mixer without it touching the bottom of the pan. Fill the pan with ~2” water, but don’t let the bowl touch the water. Heat over medium heat until the water reaches a simmer.

5. In the meanwhile, combine the eggs, salt and sugar into your mixing bowl. Whisk together and place it over the saucepan of water. Keep on whisking until the mixture is hot to the touch (120oF), which will take 5-7 minutes.

6. Remove the bowl from the saucepan and place into mixer stand. Using the whisk attachment, mix on medium-high speed (“8” on my KitchenAid mixer) until the batter is: 1. pale yellow; 2. tripled in volume and 3. drips off the whisk in wide ribbons that dissolves slowly back into the surface of the batter. (see below)


7. When the batter is ready, fold in the flour/cornstarch mixture (step 3) in 3 batches into the batter. Mix from bottom to top to ensure even distribution of flour. [Elizabeth advises not to scrape down the sides of the mixing bowl wall to remove any flour that ends up along the sides, but instead, to spread the batter along the sides of the bowl to incorporate the flour stuck on the sides. This will help prevent lumps in the batter.]

8. Scoop out a small portion of the batter into a bowl and whisk in the melted butter (step 2). Then mixed the butter/batter mixture back to the main batch of batter, mixing carefully as to not to deflate the batter.

9. Pour the batter into the prepared springform pan (step 1). Bake for ~40-45 minutes, or when the top of the cake springs back slightly when pressed. Cool the cake in the pan on a wire rack.

Go ahead and prepare the pastry cream while the cake cools.

Part 2: Pastry Cream
This recipe makes 2 ½ cups of cream…perfect because that’s how much I need to assemble the entire cake!
Ingredients
2 cups of whole milk
½ a vanilla bean
¼ tsp of salt
3-4 Tbsp of cornstarch
½ cup + 1 Tbsp of sugar
2 large eggs
4 Tbsp of unsalted butter

1. Have a bowl and a fine-mesh sieve handy for when the pastry cream is finished.

2. In another bowl (preferably one that has a rubber-grip bottom), whisk together cornstarch and sugar (more cornstarch if you want a stiffer cream). Add eggs and whisk till smooth.

3. In a heavy saucepan, add the milk, vanilla bean scrapings, and salt, and heat on medium-high heat until the mixture is just under a boil. Stir occasionally to make sure that the milk does not burn or stick to the bottom.

4. When the milk mixture has almost reached a boil, slowly ladle 1/3 of it into the egg mixture (step 2), whisking constantly (the rubber grip on the bottom of the bowl should help with the challenge of pouring and whisking at the same time).

5. Pour the egg/milk mixture back into the hot milk, whisking constantly until the mixture thickens (~2 minutes). Continue heating until the mixture is just starting to boil (you should see a few bubbles); be careful not to heat too vigorously or the eggs will curdle.

6. Once the mixture just starts to boil, immediately remove it from the heat and pour the cream through the sieve into the bowl (step 1). (Use a spoon to push the cream through the sieve if its too slow). Cool and stir occasionally to prevent a “skin” of cream from forming on the top.

7. When the pastry cream has cooled to ~140oF (10 minutes), whisk in the butter, one tablespoon at a time. Make sure the butter is well-incorporated into the mix before adding the next.

Part 3: Assembling the cake
Ingredients
1 Génoise cake (Part 1)
Assorted berries, stems removed

Fruit puree or liquor syrup:
½ pint of berries + ¼ cup of sugar + a pinch of salt
or
½ -2 tablespoons of sugar + ½ cup of water + 2-4 tablespoons of fruit-flavored liquor

Filling:
1 ½ tsp of gelatin
1 tsp of water
2 ½ cup of Pastry Cream (Part 2)
2 cups of heavy cream (very cold)

Topping:
1 ½ cups of heavy cream (very cold)
4 tsp of sugar

1. Using a serrated knife, slice the génoise cake in half horizontally using a sawing motion.

2. I decided to go with a liquor-based syrup to moisten the cake instead of the fruit-puree (what can I say, I like liquor ;)). To do this, put ½ cup of sugar minus 2 tablespoons into a small saucepan. Add ½ cup of water and bring to a boil. Stir to dissolve the sugar. Cool in fridge then add 2-4 tablespoons of your liquor of choice (mine was Grand Marnier). If you want to make the fruit puree, blend the berries, sugar, and salt in a blender until smooth.

3. To prepare the filling: prepare the gelatin by adding 1 ½ tsp. of gelatin with 1 tablespoon of water (gelatin will absorb all the water to form a gel). Then take ½ cup of the pastry cream you just made and add it to a stainless steel bowl over a saucepan of water (I used the same one that I used for making the pastry cream). Warm over medium heat, whisking constantly until hot to the touch (120oF; 5 minutes). Add the moist gelatin, and whisk until it is completely added. Remove the bowl from the water bath and add in the remaining pastry cream in two batches.

4. In a mixing bowl, whip with stand mixer on medium-high setting (“8” on my Kitchenaid mixer) the heavy cream until it holds medium-stiff peaks (see below). Then fold gently into the pastry cream with pastry cream.

5. To assemble the cake, place one half of the cake base in the bottom of a springform pan lined with plastic wrap (see results and discussion below). Moisten the cake with the prepared syrup of fruit puree with a pastry brush. Add ~1/2 of the pastry cream and even out with rubber spatula. Add the prepared fruit (I used whole strawberries and blueberries, pushing the stemless end of the strawberries into the cream).


5. To assemble the cake, place one half of the cake base in the bottom of a springform pan lined with plastic wrap (see results and discussion below). Moisten the cake with the prepared syrup of fruit puree with a pastry brush. Add ~1/2 of the pastry cream and even out with rubber spatula. Add the prepared fruit (I used whole strawberries and blueberries, pushing the stemless end of the strawberries into the cream).

6. Add the remaining filling and smooth over fruit. Moisten the last layer of cake and place it on top of the filling. Press gently into the pan to smooth out the filling. Wrap up the cake and refrigerate for 4 hours or preferably overnight.

7. When ready to serve the cake, prepare the topping by whipping the heavy cream in a stand mixer until thickened, then add sugar and continue whipping until the cream holds soft peaks. Using a rubber spatula, transfer cream onto cake and smooth out with off-set spatula.

Experiment #1: Summer Fruit Bavarian

*Note about my titles: I have labeled each section of my baking experiments as I did when I was taking chemistry lab; we were required to prepare for the labs ahead of time by writing a pre-lab and procedure so that we would know what to do when we got into lab. After the experiment was done, we would do our calculations, analysis etc., then we would have to reflect on the success of our experiment by writing a results and discussion, and a conclusion. Ask anyone that’s ever taken chemistry and they can tell you that laboratory is very time consuming! But it helped me develop some good lab skills as a chemist and I think it’s a good guide for me to learn/grow as a baker!*

Pre-Lab

The first task in starting my experiment was to pick a recipe to try; not an easy first task given the many delicious-looking treats in the book. I have the tendency to overwhelm myself with too many recipes at once, so I decided to pick the Summer Fruit Bavarian cake, which incorporates several components to keep me busy, but the end result is only one cake (good; I don’t need more than one cake in my stomach!)

I had never heard of the term Bavarian until I picked up this book but after reading it’s description as a cooked fruit-and cream or an egg-and-cream filling, I realized that I’ve probably had it sometime in my sweet-eating quests, but never knew what it was called. The cake is composed of a cake base, either a Génoise or Chiffon, the first being a French egg-based cake and the second being a lighter American cake made with lots of egg whites. Since the author Elizabeth Prueitt mentioned in her intro that she typically interviews new bakers by asking them to make a génoise and a pastry cream, I thought that I should go with the génoise (hey you never know) and of course the Pastry Cream, which is stabilized with gelatin to make the filling. I’ve never worked with gelatin before (except making Jello, if that counts), and I took it for granted what it was exactly, so I looked it up and found out that it’s a protein related to collagen (I know, that’s bio, not chemistry!)

OK so to prep for this experiment, I read the recipes for the Summer Fruit Bavarian, Génoise and the Pastry Cream. But not just reading, but actually studying and visualizing each step and trying to get myself organized for this endeavor. I looked at what equipment I needed to get, how many pints of heavy cream I would need to buy overall, and which bowls I would need to use (and when I would have to re-wash them during the process since I don’t have the luxury of having a bakery’s worth of equipment). Most importantly, I have to see what steps I need to do first (see Experimental Procedure in the next post). Funny, I do this when I’m setting up real experiments in the lab too; I have to order the right amounts of the chemicals I need and get all my equipment lined up so that they are ready to use at the time I need them. Only difference is that I can’t eat what I make in the lab. :P

From Chemist to Baker

GraceFace is my college nickname (though I'm not quite certain which of my friends came up with it)... In any case, all my friends know me to have a major sweet tooth; I am a firm believer that there is ALWAYS room for dessert ;) and I have not been shy to reveal the number of root canals I have survived over the years (3).

And so it is natural that started learning how to bake my favorite sweet treats once I had my own kitchen to experiment. By day I was working in the chemistry lab trying to make new drugs (legit one I assure you) and by night, I was baking cookies and tarts and cakes (oh my!). I brought so many baked goods to work that my co-workers called me "Betty Crocker" (I think that was a compliment!)

And so after almost 7 years of being a chemist, I am finally going to transition myself to baking, which is surprisingly not so different from what I learned in college. While I dream about professional pastry school, I'm going to practice making fancy sweet treats on my own. My source of inspiration comes from a lovely bakery here in San Francisco called Tartine. Though I've only eaten there once, the beauty of the pastries in their book is inspiring and this is where I will begin my baking journey!