Chocolate Mocha Cake with Fudgy Frosting

Be prepared to swoon, chocolate lover.

This is the chocolate cake recipe that you will adopt as your own, so you might as well print it out right now and laminate it. You’ll bake this cake for your own birthday parties (tacky, but worth it), you’ll start eating it for breakfast (if you happen to have a piece left over in the morning), and you’ll find yourself craving it in the middle of the night when you get up to go to the bathroom (explaining why you might not have any left for breakfast).

This is the chocolate cake that’s decadently dense and rich- so much so that I was told “I love these brownies!” when serving last week (don’t get me started on brownies- I am forever married to the World’s Greatest Fudge Brownie recipe and can’t fathom a cakey brownie as an acceptable dessert experience). And how appropriate is it to slather a fudgy cake with an even fudgier icing- one that literally pours over the cake in a strangely seductive fashion? Oh, it’s appropriate, and it’s happening in this recipe.

Major recipe bonus: this classic is really easy to make, since you melt the butter (which we all know is way easier and faster than having to let the butter come to room temperature first), and if you’re really risque, you can do it all by hand (what? skipping the stand mixer? sorry KitchenAid).

Recipe adapted from the good people at King Arthur Flour…

1 cup unsalted butter (2 sticks)
1/2 cup unsweetened Dutch-process cocoa (I use the Double-Dutch Dark Cocoa from King Arthur Flour)
1 cup hot water
2 cups all-purpose flour
2 cups sugar
1 tablespoon instant espresso powder (or 1 1/2 tablespoons instant coffee granules)- optional
1 1/2 teaspoons salt
1 teaspoon baking soda
1/2 cup buttermilk
2 large eggs
2 tablespoons Kahlua (or other coffee liqueur)- optional
1 teaspoon vanilla

FUDGY FROSTING:
1/2 cup unsalted butter (1 stick)
1/4 cup unsweetened cocoa
6 tablespoons buttermilk
4 cups confectioners’ sugar
1. Preheat oven to 350°, and grease a foil-lined 9 x 13″ cake pan.
2. In a medium bowl, melt butter in microwave and then stir in cocoa powder and hot water (fresh from being boiled). In a separate medium bowl, combine the flour, sugar, espresso powder (if using), soda and salt. Pour the butter/cocoa mixture over the dry ingredients, and stir to blend. Beat in the buttermilk, eggs, vanilla and Kahlua (if using).
3. Pour batter into prepared pan and bake for 35 minutes, or until a cake tester pulls out with just a few crumbs attached; cool on a rack, then carefully remove the cake using the edges of the foil as a sling. Place on a cooling rack or serving dish.
4. Frosting: melt butter in a medium-sized saucepan, and stir in the cocoa and buttermilk. Bring the mixture to a boil, then remove from the heat and mix in the confectioners’ sugar, beating until smooth. Pour over the cake while the frosting is still warm.
Tips:
- Double-Dark Dutch? Cocoa powder is a funny thing- there’s the natural kind and there’s the Dutch-processed kind. While there is a time & place for both, this recipe definitely calls for the Dutch-processed variety, as it’s less bitter than its natural counterpart (and some kind of science lesson says that the addition of alkali- to neutralize cocoa’s acidity- impacts how the cake rises. sorry, who cares, right?). I am a serious fan of the KAF “Double-Dutch Dark” powder- it’s crazy dark and rich, but you can also find a dark version from Hershey’s if you’re shopping at the grocery store. If you can’t find a dark cocoa powder, just make sure to get a brand that is Dutch-processed, that’s all.
- Want to skip the mocha and keep it pure? No problem! Just skip the espresso powder and the Kahlua… the cake will still be divine. (But I will say that the addition of the espresso powder is recommended as an almost imperceptible flavor enhancer, that takes chocolate up a notch or two. It’s like how salt is necessary in a sweet recipe- a balancer of sorts. That’s all for my espresso powder campaign.)
- Uh oh. No buttermilk. It’s okay- just pour regular milk into a measuring cup, less a tablespoon or so. Add lemon juice or vinegar to equal the total amount you’re looking for. Wait a few minutes and stir… voila. Buttermilk (sort of). (So in this recipe, you want 1/2 cup for the cake and another 6 tablespoons for the icing- so pour about 3/4 cup of milk into a measuring cup and add two tablespoons of vinegar or lemon juice.)
- Oozey frosting: this cake is breathtaking to me in large part because of the frosting. You really will want to pour it and then spread it while it’s warm, so it oozes as intended. fool around with the icing sugar amounts- if you want a runnier icing, then use less. If you want a stiffer icing that you need to spread with a spatula, add more. (Idea: why not poke holes in the cake and make a runnier icing that fills the holes up in an “exciting surprise when cutting into the cake” way? For that matter, you could pour some of the icing when runny over the top of the hole-poked cake, then add more sugar to the remaining icing in the bowl and spread that over the cake so there’s a bit more substance.)
- To remove the cake from the pan, or not remove the cake from the pan… if you want to serve pieces that have the frosting dripping off the edges, you’ll want to remove the cake before frosting (and just make sure that some of the frosting cascades over the sides— just nudge it with a spatula). If you want to make life easier, just pour the icing over the cake after it has cooled in the pan. (Idea: if you really like the idea of the icing doing the Niagara Falls thing over the edge of the cake, why not cut the pieces up, put them on serving plates, and pour the icing over each piece? Pour the frosting over the remaining hunk of cake in the pan that you’re not serving right away.)
- Enjoy!
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April 7th, 2012 | More Sweets Please | 2 Comments | Tags: Cakes, Chocolate, Classics, Icing

2 Responses and Counting...

R Ruel 04.07.2012

If they ever hold a worldwide baking competition, your recipe for chocolate mocha cake with fudgy frosting will win olympic gold. It’s the best cake I’ve ever tasted.
More Sweets Please

Wow- that’s quite the endorsement… thank you for your vote! Eat up, mocha lover!