Instructions:

1. Preheat the oven – Preheat your oven to 350°F (175°C) and line a 12-count muffin tin with cupcake liners.
2. Mix the dry ingredients – In a bowl, whisk together flour, baking powder, and salt. Set aside.
3. Cream the butter and sugar – In a large bowl, beat butter and sugar together until light and fluffy.
4. Add eggs and vanilla – Mix in eggs one at a time, then add vanilla extract and beat until smooth.
5. Combine wet and dry ingredients – Gradually add the dry ingredients, alternating with milk, and mix until just combined.
6. Bake the cupcakes – Fill cupcake liners ¾ full and bake for 18-20 minutes or until a toothpick inserted in the center comes out clean. Let cupcakes cool completely.
7. Make the pastry cream – Heat milk and heavy cream in a saucepan until hot but not boiling. In a bowl, whisk sugar, egg yolks, and cornstarch. Slowly pour the hot milk into the egg mixture, whisking constantly, then return to heat and cook until thickened. Stir in vanilla extract and butter. Cool completely in the fridge.
8. Fill the cupcakes – Cut a small hole in the center of each cupcake. Pipe chilled pastry cream inside, then cover the hole with the removed cupcake piece.
9. Prepare the ganache – Heat heavy cream until warm, then pour over chocolate chips. Let sit for 2 minutes, then stir until smooth. Add corn syrup if using.
10. Top the cupcakes – Spoon chocolate ganache over the filled cupcakes. Let set before serving.