Chocolate Angel Food Cake with Kahlua Sauce

Baking a lot of key lime pies left me with a lot of egg whites leftover, so I made this. Low calorie but wonderfully flavorful. (133 calories with less than a gram of fat per serving!)

Cake:
9 egg whites
3/4 teaspoon cream of tartar
1.5 teaspoons vanilla extract
1 1/8 cup sugar
4.5 tablespoons cocoa
1/4 teaspoon cinnamon

Sauce:
3/8 cup sugar
1.5 teaspoons cornstarch
1.5 cups skim milk
1 egg, beaten
3 tablespoons Kahlua (or other liqueur of your choice)

Sift together flour, cocoa, 3/8 cup sugar and cinnamon, set aside. Beat egg whites with electric mixer until foamy, add cream of tartar and beat until soft peaks form. Gradually add 3/4 cup sugar, beating continuously until stiff peaks form. Fold in dry ingredients and mix completely. Pour into ungreased tube pan. Bake at 375 for 20-25 minutes. Invert and cool for at least 30 minutes before removing from pan.

For sauce, dissolve 3/8 cup sugar and cornstarch in cold milk; whisk in egg. Cook to boiling over low heat, stirring continuously. Boil one minute ,then remove from heat and whisk in Kahlua. Serve cake slices with a tablespoon of sauce and sliced berries, if desired. Makes 15 1 inch pieces. Serves 15.