Chocolate Sour Cream Frosting
Ingredients: 

2 ounces Ghirardelli 100% Cacao Unsweetened Chocolate Baking Bar
1/2 cup sour cream
3 cups sifted powdered sugar
1 teaspoon vanilla

Directions

Beat sour cream with sugar and vanilla until smooth. Mix in melted chocolate. Spread over 9" x 13" cake. Store in refrigerator.