Mix as directed, except, fold in 2 quares (1 ounce each) unsweetened chocolate, coarsely shaved.
When cake is baked and cooled, fill with Dark Chocolate Filling.
Dark Chocolate Filling
1 cups sugar
1/3 cup cream
2 Tbsp butter
2 squares (1 ounce each) unsweetened chocolate, cut up
2 egg yolks, beaten
In medium saucepan, mix suagr, cream, butter and chocolate. Cook over medium heat, stirring constantly, until chocolate and butter are melted.
Stir half of the hot mixture into the egg yolks; stir into remaining hot mixture in saucepan. Heat to boiling, stirring constantly. Boil and stir one minute. Remove from heat; cool completely.
Fill layers with chocolate mixture.
Frost cake with Fluffy White frosting (found in the bakery aisle.) Decorate with shaved chocolate curls from a semi-sweet chocolate bar.