Put all ingredients for banana cream in a blender and blend until smooth.
Then, in a medium saucepan, heat mixture over medium heat, stirring often so the mixture does not burn. Continue stirring until mixture has thickened, almost like a pudding.
Remove from heat and cool completely.
Meanwhile, remove center from cupcakes. I used a handy tool that pops the centers out (you can find them the in cake decorating aisle of many craft stores) but you can also just use a teaspoon. You want only about a teaspoon or a little more out. Save the popped out cake for another use (or eat them, like we did!)
Prepare icing. Divide in half and add ½ cup cocoa powder to one portion to make chocolate icing.
Add a couple of drops of black food coloring to chocolate icing and blend until you achieve desired shade.
Add to decorator’s bag and pipe out using #4 size tip to frost top of cupcakes.