Dirty Banana Cake

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“The 'dirt' on this cake is that it's wonderful! Actually, it's the coffee frosting...a 3-layer banana cake filled with banana buttercream and iced with that wickedly dirty frosting...2DIE4!”

Ingredients Nutrition


  1. Place oven rack in bottom third of oven and preheat the oven to 350F; line a 9 X 3 inch round cake pan or springform pan with wax paper and grease the paper; (If using a springform pan that doesn�t seal tightly, wrap the bottom with foil to prevent leakage).
  2. Make the banana cake: Sift together the flour, baking soda, baking powder and salt; in a large bowl, cream the butter with the sugar at medium speed until smooth; add the eggs one at a time, beating for 1 minute after each addition; in a bowl, mash the bananas with the buttermilk; beat the dry ingredients into the butter at medium speed in two additions, alternating with the bananas (the batter may appear slightly curdled � that�s OK); Pour the batter into the prepared pan and smooth the top; bake in the bottom third of the oven for about 1 hour, or until it tests done; (MAKE AHEAD: The cake can be made 1 day ahead; wrap in plastic wrap and store at room temperature.).
  3. Make the banana buttercream filling: In a large bowl, beat the egg yolks and confectioners� sugar at high speed until pale and thick; meanwhile, in a medium saucepan, bring the milk and banana to a boil over medium heat, whisking occasionally; slowly whisk the hot milk into the egg yolks; pour the mixture back into the saucepan and cook over medium-low heat, stirring, until thick, about 5 minutes; do not boil; transfer the custard to a medium bowl and let cool briefly, whisking occasionally; then press a piece of plastic wrap directly on the surface of the custard and refrigerate until chilled, atleast 3 hours or overnight; bring close to room temperature before continuing, otherwise, your buttercream will curdle. Beat the butter at high speed until fluffy; Reduce the speed to low and gradually mix in the cold banana custard; beat at medium speed until fluffy, then beat in the espresso.
  4. Assemble the cake: Split the cake into 3 equal layers (they will be quite thin); place one layer on a cake plate and cover with half of the banana buttercream filling; top with a second cake layer and the remaining filling; place the third cake layer on top, cover with plastic wrap, and refrigerate.
  5. Make the coffee frosting: In a large, heatproof bowl, beat the sugar and egg whites until mixed; place the bowl over a large saucepan of simmering water; do not let the bowl touch the water; heat the mixture, whisking occasionally, until the sugar is dissolved, about 5 minutes; remove from the heat and beat at high speed until fluffy, about 3 minutes; Beat the meringue at medium speed until cool to the touch, about 5 minutes; Beat in the butter several pieces at a time, waiting until they are incorporated before adding more; whip the frosting until fluffy; (if the frosting appears lumpy, beat at high speed until smooth; If the mixture is soft and runny, refrigerate for 6-8 minutes, then beat again) beat in the espresso and vanilla until blended; set aside ½ cup of the frosting for decorating; spread the remaining frosting on the sides and top of the cake; with the reserved frosting, using a pastry bag fitted with a star tip, pipe 8 rosettes on the top edge of the cake; Place 1 chocolate-covered espresso bean in the center of each rosette; to serve: Slice gently with a serrated cake knife (MAKE AHEAD: the cake can be refrigerate for 1 day; let stand at room temperature for 1 hour before serving).

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