Classic Chocolate Layer Cake

INGREDIENTS

For the cake:

1 1/4 cups

all-purpose flour

1 cup

unsweetened cocoa powder, plus more for dusting the pans

2 tsp

instant espresso or coffee powder

1 cup

boiling water

1/2

cup sour cream

2 tsp

vanilla extract

1 cup

unsalted butter, at room temperature

1 3/4 cups

sugar

large eggs, at room temperature

1 tsp

baking soda

1/2

tsp. salt

For the frosting:

9 1/2 oz

bittersweet chocolate, finely chopped

6 oz

cream cheese, at room temperature

6 tbsp

unsalted butter, at room temperature

2 cups

confectioners’ sugar, sifted

4 tbsp

unsweetened Dutch-process cocoa powder

salt

2/3 cup

plus 1 tbsp. sour cream