1/2 cup unsalted butter
2 1/2 cups all-purpose flour
1/2 cup unsweetened cocoa powder or Dutch processed cocoa powder
1 1/2 teaspoons baking soda
1/4 teaspoon salt
1 cup granulated sugar
1 cup packed brown sugar
2 teaspoons vanilla
1 cup buttermilk or sour milk (see note)
1/2 cup boiling water
Whipped cream (optional)
Small whole strawberries and/or red raspberries (optional)
1. Allow butter and eggs to stand at room temperature for 30 minutes. Meanwhile, grease a 13x9x2-inch baking pan. In a medium bowl, stir together flour, cocoa powder, baking soda and salt. Set aside.
2. In a large mixing bowl, beat butter with an electric mixer on medium to high speed for 30 seconds. Add granulated sugar, brown sugar and vanilla. Add eggs 1 at a time, beating well after each addition. Alternately add flour mixture and buttermilk to butter mixture, beating on low speed after each addition just till combined. Add boiling water; beat till smooth. Pour batter into prepared pan.
3. Bake in a 350 degree F oven for 30 to 35 minutes or till a wooden toothpick inserted near center comes out clean. Cool thoroughly in pan on wire rack.
4. Serve with whipped cream and strawberries, if you like, or your favorite flavor ice cream. Or, frost with desired cake frosting. Makes 12 to 16 servings.
Making Sour Milk: If you dont have buttermilk on hand when preparing baked goods, substitute sour milk in the same amount. For each cup of sour milk needed, place 1 tablespoon lemon juice or vinegar in a glass measuring cup. Add enough milk to make 1 cup total liquid; stir. Let mixture stand for 5 minutes before using.