Quick Weeknight Cake with Amazing Icing

1 box Jiffy brand yellow cake mix

1 egg

1/2 cup water

1 cup mini marshmallows (optional)

Icing:

7 tablespoons butter

1/4 cup cocoa powder

1/2 teaspoon vanilla
3 tablespoons milk

1 1/2 cups powdered sugar

Prepare cake as directed on box except stir in 1 cup mini marshmallows (optional) before pouring batter into a round cake pan.

I totally cheated and put my cake in the freezer straight out of the oven.  Left it in there for about a half hour.  But you don't have to let it cool first, you can apply the icing even if the cake is still warm.

Leave the cake in the pan.

Melt butter in a small saucepan and stir in cocoa powder and vanilla.  In a bowl whisk cocoa/butter, milk and powdered sugar together until smooth and pour over top of cake.