1 (15.25- to 16.5-ounce) package yellow cake mix
3 to 4 (1 1/4 cups) very ripe bananas, mashed
1 cup sour cream
1/4 cup vegetable oil
2 (1-ounce) squares unsweetened chocolate, melted, cooled slightly
2 teaspoons vegetable oil
6 cups powdered sugar
1 tablespoon light corn syrup
2 teaspoons vanilla
Mini pastel colored decorator sprinkles or decorator sugars
Curling ribbon, if desired
Heat oven to 350°F. Line 13x9-inch baking pan with aluminum foil; grease and flour foil. Set aside.
Combine all cake ingredients except chocolate and oil in bowl; beat at medium speed until well mixed. Reserve 2 cups batter; set aside. Spread remaining batter into prepared pan.
Combine melted chocolate and oil in bowl until well mixed. Stir into reserved batter; mix well. Drop by spoonfuls over batter in pan; using table knife, swirl chocolate batter into banana batter.
Bake 33-38 minutes or until toothpick inserted in center comes out clean. Cool completely. Freeze 1 hour.
Meanwhile, combine all frosting ingredients except half & half in bowl. Beat at medium speed until well mixed. Continue beating, adding enough half & half for desired spreading consistency.
Remove cake from freezer; carefully invert onto large 15x10-inch platter. Frost top and sides with about 2 1/2 cups frosting. Place remaining frosting in pastry bag fitted with large 3/4-inch star tip. Pipe large stars onto frosting on outside edge of cake. Sprinkle with decorator sprinkles.
Place 7 or 8 large gumballs on cake for balloons. Place licorice pieces under gumballs for strings. “Tie” strings with licorice, if desired.
Let stand at room temperature for 2 hours before serving.
- Freezing the cake for 1 hour makes it easier to work with. A frozen cake helps reduce the risk of cracks occurring in the cake as it is inverted onto a platter. It is also easier to frost.
- If you don’t have a large platter, cover a large sturdy piece of cardboard with aluminum foil.