When it comes to birthday cakes, I just didn't think you could beat chocolate cake with chocolate frosting ... until I had chocolate cake with fudge frosting! This isn't the chocolate fudge frosting that comes out of a can and it's certainly not your average buttercream. This is full-on fudge, cooked, cooled, and spread on thick!
Bless America's Test Kitchen for enlightening me with this recipe (and all their other recipes in the Chocolate Desserts collection). I hereby swear that I will never make another chocolate frosting. We celebrated two birthdays at the office this week, which was a perfect occasion for this confection. But despite those birthday celebrations, I hoarded this cake in my office so I only had to share it with a select few!
Wellesley Fudge Cake
2 1/2 cups flour
2 teaspoons baking soda
1 teaspoon baking powder
1/2 teaspoon salt
3/4 cup hot water
1/2 cup cocoa powder
1 cup (2 sticks) unsalted butter, softended
2 cups sugar
1 cup buttermilk
2 teaspoons vanilla
1 1/2 cups brown sugar
1 cup evaporated milk
1/2 cup (1 stick) butter, softened
1/2 teaspoon salt
8 oz. bitterwseet chocolate1 teaspoon vanilla
3 cups confectioners' sugar
Adjust oven rack to middle position and preheat oven to 350 degrees. Grease and flour 2 8-inch square cake pans. Combine flour, baking soda, baking powder, and salt in bowl. Set aside. In another bowl, whisk hot (not quite boiling) water with cocoa powder until smooth. Set aside. Using stand mixer fitted with paddle attachment, beat butter and sugar on medium-high speed until light and fluffy. Add eggs, 1 at a time, and mix until incorporated. Add flour mixture in 3 additions, alternating with 2 additions buttermilk. Mix until combined. Reduce speed to low and slowly add cocoa mixture and vanilla until incorporated.
Divide batter evenly between pans and smooth tops with spatula. Bake until toothpick inserted in center comes out with just a few crumbs attached. (Note: The recipe called for a cooking time of 25 to 30 minutes. My cakes took closer to 40 minutes, and I don't think it's the fault of my brand new, spiffy oven.) Let cakes cool in pans 15 minutes, then turn out onto wire rack. Let cool completely, about 1 hour. (Another note: I let my cakes cool completely in their pans and the bottoms ended up sticking and requiring a minor repair job in the frosting stage. I used plenty of cooking spray and flour so I'm not sure what happened, but next time I will attempt to turn them out earlier.)
For the frosting, heat brown sugar, 1/2 cup evaporated milk, 4 tablespoons butter, and salt in large saucepan over medium heat until small bubbles appear around perimeter of pan, 4 to 8 minutes. Reduce heat to low and simmer, stirring occasionally, until mixture has thickened and turned deep golden brown, about 6 minutes. Transfer to large bowl. Cut remaining butter into 4 pieces and stir in with remaining evaporated milk until mixture is slightly cool. Add chocolate and vanilla and stir until smooth. Whisk in confectioners' sugar until incorporated. Let cool to room temperature, stirring occasionally, about 1 hour. (Warning: You will be eating spoonfuls with every stir. It's impossible to resist.)
Place 1 cake square on serving platter. If necessary, use a sharp, serrated knife to level the top of the cake. Spread 1 cup frosting over cake, then top with second cake square. Spread remaining frosting evenly over top and sides of cake. Slice (or not) and dig in!