Preheat your oven to 350°F (175°C) and line a muffin tin with cupcake liners.
In a large bowl, cream together the butter and sugar until light and fluffy. Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.
In another bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the wet ingredients, alternating with the milk. Mix until just combined.
Fill each cupcake liner about ⅔ full with the batter. Bake for 15-18 minutes, or until a toothpick inserted into the center comes out clean. Allow to cool completely.
For the cookie dough filling, cream together the butter and sugars until light and fluffy. Mix in the flour and vanilla extract until well combined. Stir in the mini chocolate chips.
Once the cupcakes are cool, use a small knife to cut out a small hole in the center of each cupcake. Fill each hole with the cookie dough mixture.
Serve and enjoy!