black walnut potato cake

Ingredients

• CAKE:
• 2 cups sugar
• 4 large eggs, separated
• 2 teaspoons baking powder
• 1 teaspoon nutmeg
• 1 cup cocoa powder
• 1 cup mashed potatoes
• 1 cup walnut pieces
• 1 cup raisins
• 1 teaspoon pure vanilla extract
• 3/4 cup butter
• 2 cups all purpose flour
• 1 teaspoon cinnamon
• 1/4 teaspoon salt
• 1/2 cup milk
• FROSTING:
• 1/2 stick butter
• 2 squares - semi-sweet baking chocolate
• 2 - 3 cups confectioners' sugar