Let me just get this out of the way right off the bat: I don't really like chocolate cake. It's always just a little wrong somehow--too dry, not chocolately enough (just, you know, chocolate-colored), too rich, too sweet, too something.
I needed to make my peace with chocolate cake.
There are so many kinds of chocolate cake out there. Americans prefer a sweet, soft, light cake--like the box mix. In fact, box mix seems to be the standard to which all homemade cakes are measured, strangely. It's a texture thing. American cakes have to be light and moist, which is tough for butter-happy homebakers (butter is a huge factor in why homemade cakes are often dry--more on this later).
Australian chocolate cake is mud cake--dense, rich, almost brownie-like to us. And in Europe, most chocolate cake is either a flourless torte or it's dry as a hard sponge--and why it's often soaked in liquor syrup or simply meant to be dunked in tea. There's a place for all of it.
I had a very specific set of criteria for the perfect chocolate cake: it has to be very flavorful, first of all, and it has to be moist but not dense. It has to have a fine, velvety crumb, with a soft but sturdy texture so it can be stacked, carved, and covered in heavy ganache and fondant. Most American chocolate cake recipes are great for cupcakes or sheetcake that does not get torted and carved--it has an open and squiggly crumb that is deliciously soft but terrible for tall, stacked cakes.
We're going to need cake flour for softness, a bit of sour cream, both cocoa powder and melted chocolate for the best flavor, and mostly oil instead of butter. Butter, while I love it to death, has a higher water content than oil (obviously) and also has those pesky solids--the whey--that harden the cake's sugar-fat-flour bonds. A thousand recipes later, balance was finally achieved.
The recipe starts with the melted-sugar method of which I am such a fan, and to the hot sugar the chocolate is added, so no extra melting step is required, conveniently. I decided to add the sour cream to the whipped cream that gets folded in and the end and it helped to keep the cake light and flavor-balanced.
The recipe is dairy and egg heavy, so swapping in some gluten-free flour is going to work just fine, but a non-dairy, egg-less version I believe would not be possible. You also have a good bit of sugar here, so make sure you are using unsweetened chocolate and not semi-sweet as a substitute. The espresso powder is optional but definitely boosts flavor, and I promise does not impart a coffee taste.
Just to be sure I'd found tough-yet-tender perfection, I made an extra tall cake with custard buttercream and wrapped it in a heavy and dramatic molded fondant design.
Look at this piece! I made a silicone mold of a vintage wooden architectural detail I'd found in my mold-making madness that I knew would be absolutely killer on a cake. Typically fondant molds are little, fussy affairs, made from jewelry findings and meant to be arranged judiciously as appliques. This mold, on the other hand, makes the cake in one fell swoop.
This recipe makes a LOT of cake--about 9 cups of batter, so feel free to halve it if you are only making a small cake. It will fit four 9" pans generously, or--as I have done here with this cake--two 3" deep 6" pans and two regular 4" pans. I can't recommend enough to get yourself some deep cake pans rather than the standard piddly shallow ones. You'll save space in your oven, since more layers can come out of one pan, and they help prevent overcooking/dry cakes. Using a flower nail or heating core in the center of a deep pan will ensure your cakes cook evenly.
This cake takes a syrup soak really well, and I highly recommend it, since all chocolate cake is prone to drying due to the chocolate itself. Just make a simple syrup, add the flavoring or extract or liquor of your choice, and brush or squeeze on before icing.
Perfect Chocolate Cake
14.2 oz. cake flour (I use White Lily)
16 g. (about 4 tsp) aluminum-free baking powder
1 oz. (about 1/2 c.) cocoa powder
3/4 c. heavy cream
1/4 c. sour cream
21 oz. (about 3 c.) granulated sugar
2/3 c. water
2 tsp. instant espresso powder
4 oz. unsweetened chocolate, chopped finely
2/3 c. plus 3 Tbsp. canola oil
4 Tbsp. unsalted butter, softened to room temp
1 tsp. salt
1 Tbsp. vanilla extract
6 yolks, room temp
4 eggs, room temp
Preheat oven to 350 degrees and prepare pans. With a hand mixer, mix the flour, baking powder, and cocoa powder thoroughly, until no lumps remain (do not skip this step, it is especially important with cocoa and cake flour which both tend to clump). Rinse beaters and use to whip cream in a cold bowl to soft peaks, add sour cream and whip to firm peaks. Place whipped cream in the fridge. Chop chocolate finely.
In a saucepan, heat sugar, water, and espresso powder over medium heat until most of the sugar is dissolved. Stir frequently or use your hand mixer to speed up the process (be careful that the cord is kept away from the burner). Do not allow mix to boil. Once the sugar is mostly dissolved, pour into a large bowl and add chocolate, mixing until smooth. Add salt, vanilla, oil, and butter and mix until smooth. Sprinkle 1/3 of the flour mix into the wet ingredients and mix well on low, then gradually add the rest but do not overbeat. Set mixer aside and grab a spatula and whisk. At this point, the mixture should be warm but not too hot to touch--If your sugar mixture is still very hot, allow it to cool--you don't want to cook your eggs.
Add the yolks next, two at a time, mixing in by hand with whisk, then the eggs. Don't be tempted to reach for your electric mixer. Just be patient. They incorporate better if they are room temperature instead of cold from the fridge. Then gently fold whip cream into the mixture with a spatula until completely combined. Pour into prepared pans and tap them hard several times on the counter to release large air bubbles. Bake anywhere from 20--45 minutes depending on your pan sizes and depth. Cakes are done when their centers spring back, they no longer jiggle when moved, and the edges just begin to pull away from the sides. I don't recommend poking anything into your cakes to test doneness--just a quick press with your finger in the center will tell you all you need to know. Deep pans will also cause the tops to split (see my photo) which is another good indication of doneness. Cool, level, and split cakes, then soak with simple syrup and frost.