Preheat oven to 350°F and place paper liners in muffin tin or grease and flour cupcake pans.

In a medium sized bowl, sift together flour, baking powder, and salt. Set aside.

Cream the butter with an electric mixer for 1 minute. Add the sugar and mix for 2 more minutes until light and fluffy. Add the vanilla.

Add the eggs one at a time, mixing well after the addition of each egg.

Alternatively add the dry ingredient mixture and milk to the sugar mixture, mixing well after each addition and be sure to scrape down the sides of the bowl.

Fill cupcake liners about 3/4 full.

Bake for 15-20 minutes, until a toothpick comes out clean when inserted into the center of a cupcake. Cool for about ten minutes in the muffin tins and then remove to a rack to cool completely.

Once cupcakes are cooled, core them (save the tops for bite sized snacks). I like to use a cupcake corer for this, but you can also just use a knife. 

Combine the sugar, cornstarch, flour, and salt  in a medium saucepan. Slowly stir in the milk. Turn the heat on to medium. Stir constantly until the mixture comes to a boil. Cook 2 minutes. Remove from heat. 

In a medium heatproof bowl, use a fork to beat the egg yolk. Slowly stir a small amount of the hot milk mixture into the egg yolk to warm the egg yolk. Immediately pour the yolk mixture back into the remaining hot mixture. Stir to completely combine. Stir constantly as you cook 2 more minutes. Remove from heat. Stir in butter and vanilla. Pour mixture in a heatproof bowl and place a piece of plastic wrap directly on top of the warm filling to prevent a skin from forming. Allow to cool for at least 15 minutes. Before using, stir in a chopped medium ripe banana. 

Place your mixing bowl and whisk attachment in the freezer for five minutes to chill before making the whipped cream.

Once the bowl is chilled, add all ingredients to the bowl. Beat on medium for 3-4 minutes, until you stiff peaks form (until the peaks hold their shape).