Frosting:

8 oz. semi-sweet chocolate, chopped
1/4 c. hot water
3 tbsp. light corn syrup
1/2 c. sour cream
1 1/2 c. butter (room temperature)
2/3 c. confectioners sugar

Melt chocolate in bowl set over pot of hot, not simmering, water. Measure 1/4 cup hot water. Stir in corn syrup until smooth. Stir in melted chocolate until smooth. Remove bowl from pot. Stir in sour cream. In large bowl at medium speed, beat butter until smooth. Gradually beat in confectioners sugar. Beat in chocolate mixture until smooth. Place one cake layer on serving plate. Spread with 1 1/2 cups frosting. Place second layer on top. Spread top and side of cake with remaining frosting. If frosting is too warm, put in fridge for 20 minutes or so.

Cake:

1 tsp. vanilla
1 c. boiling water

Cake: Preheat oven to 350°F. Butter and flour two 9-inch cake pans. In large bowl, combine flour, sugars, cocoa powder, baking powder, baking soda and salt. At medium speed, beat in milk, oil, eggs and vanilla until blended, about 2 minutes. At low speed, gradually beat in boiling water just until blended. Divide batter between cake pans.

Bake 25 to 28 minutes or until toothpick inserted into center comes out clean. Cool in pans on racks 15 minutes. Remove from pans. Cool on racks.