Chocolate Sour Cream Frosting Be The First To Review By Anonymous recipe Wonderful old-fashioned icing made with chocolate syrup and sour cream. Add crushed nuts for variety. Chocolate Sour Cream Frosting Ingredients 2 cups white sugar2 tablespoons chocolate syrup2/3 cup sour cream1 teaspoon vanilla extract Instructions 1 In a saucepan, combine the sugar and chocolate syrup. When well mixed, stir in the sour cream. Cook over medium heat to the soft ball stage (234 degrees F, 112 degrees C on candy thermometer). 2 Remove from the heat. blend in vanilla and beat until thick enough to spread.