Solid Chocolate Cake (Mrs. R. Heim.)

Ingredients

• 1 cup butter
• 2 cups sugar
• 6 egg yolks
• 1 cup sour milk
• 1 teaspoon baking soda
• 3 cups flour
• 6 egg whites
• 0.5 cake Baker's chocolate
• 3 teaspoons vanilla

Instructions

1. Cream together the butter and sugar. Add the beaten egg yolks.
2. Alternately add the sour milk (with the baking soda dissolved in it) and the sifted flour, incorporating each addition fully.
3. Fold in the stiffly beaten egg whites. Add the melted Baker's chocolate and vanilla.
4. Stir hard for about a minute. Pour into a deep, well-greased pan.
5. Bake in a moderate oven until done.