3 c powdered sugar
1/3 cup butter, softened
2 tsp vanilla
3 oz unsweetened baking chocolate, melted and cooled
2 to 3 Tbsp milk
Mix all ingredients except milk in medium bowl. Stir in milk until smooth and spreadable. Frosts one 13 x 9 cake generously, or fills and frosts on 8- or 9-inch two-layer cake.