Wellesley Fudge Cake II

½ cup butter

1 ⅞ cups white sugar

4 egg yolks

1 cup all-purpose flour

1 cup unsweetened cocoa powder

1 ⅓ tablespoons baking powder

½ teaspoon salt

4 egg whites

1 cup milk

2 teaspoons vanilla extract

2 cups semisweet chocolate chips

¾ cup sour cream

1 teaspoon vanilla extract

1 pinch salt

Preheat oven to 325 degrees F (165 degrees C). Grease and flour three 9 inch round cake pans.

In a large bowl, cream together the butter and sugar. Beat in the egg yolks, one at a time. Stir in 2 teaspoons vanilla. Combine the flour, cocoa, baking powder and salt, stir into the creamed mixture alternately with the milk.

In a large clean glass or metal bowl, whip egg whites until soft peaks form. Fold 1/3 of whites into batter to lighten it, then quickly fold in remaining whites until no streaks remain. Divide batter into the 3 prepared pans.

Bake for 20 to 25 minutes in the preheated oven, until a toothpick inserted into the center of the cake comes out clean. Cool in pans on a wire rack.

To make the frosting: Melt the chocolate chips in the top of a double boiler, stirring occasionally until smooth. Remove from heat and stir in the sour cream, 1 teaspoon vanilla and pinch of salt. Frosting can be used warm to fill and frost the 3 layers.