Preheat oven to 350°F and place paper liners in muffin tins.

Whisk together flour, baking powder, and salt. Set aside.

Cream the butter and sugar with an electric mixer on medium speed for 3-4 minutes until light and fluffy. Add the vanilla.

Mix in the egg.

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

Fill cupcake liners with about 1/4 cup of batter (about 2/3 full).

Bake for 16-18 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.

Lightly whisk the egg yolks in a small heatproof bowl. Set aside.

Whisk to combine the cornstarch and sugar in a medium saucepan. Over medium heat, slowly stir the milk. Cook for about two minutes until mixture comes to a boil, whisking while cooking. Remove from heat.

Add a small amount of the hot mixture into the yolks. Stir well.

Pour the egg yolk mixture into the milk mixture. Stir continuously while it cooks on low heat for 2 minutes. Remove from heat and stir in the butter and vanilla. Allow to cool completely.

Place the chocolate chips in a heatproof bowl. In a small saucepan on low heat, bring the heavy cream to a boil then pour over the chocolate chips. Do not stir.

Allow to sit for 3 minutes then stir till smooth. Allow to cool slightly before using.

Cut each cupcake in half horizontally using a serrated knife and spread 1 tablespoon of vanilla cream on the bottom of each cupcake. Place the tops back on the cupcakes.

Spoon the glaze over the cupcakes and enjoy!