Vanilla Bean Cappuccino Cake
Make the cake:
Separate the eggs, reserving the yolks for another use. Set the whites aside to come to room temperature. In a bowl combine the flour, baking powder, baking soda and salt, and set aside.
Preheat the oven to 350 F. Line the bottoms of 3 8-inch round cake pans with parchment paper (since I don't have 3 pans, I divided the batter between 2 pans with higher sides, but had to bake the cakes for longer). Spray the parchment paper with non-stick spray, but don't spray the sides of the pans.
In the bowl of your electric mixer, combine the butter, sugar and vanilla bean paste - using the paddle attachment, beat on medium speed until fluffy and well combined, about 5 minutes. Add all of the egg whites at once and beat for 3 minutes. Reduce the speed to low and gradually add the flour mixture, alternating with the buttermilk, just until combined. Divide the batter between the prepared pans.
Bake for 30-35 minutes until the center of the cake is done. Cool the cakes in the pans on wire racks for 20 minutes. Run a sharp knife around the edges then turn out onto racks, peel off the parchment paper, cover with a clean kitchen towel and cool completely before frosting.
Make the frosting:
Dissolve the espresso powder in the milk. In the bowl of your electric mixer combine the milk, butter, powdered sugar on low Increase speed to medium high and whip for 4-5 minutes until very light and fluffy.Frost the cooled cake with the coffee buttercream. If desired, garnish the top with a few sliced almonds and chocolate-covered espresso beans.