- Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with paper liners. 
- In a bowl, whisk together flour, baking powder, and salt. 
- In a separate bowl, cream butter and sugar until light and fluffy. Add eggs one at a time, then vanilla. 
- Alternately mix in the flour mixture and milk, beginning and ending with flour. Mix just until combined. 
- Divide batter evenly among cupcake liners. Bake for 18–20 minutes or until a toothpick comes out clean. 
- Let cupcakes cool completely. Then, using a small knife or cupcake corer, cut out a 1-inch hole in the center of each cupcake. 
- Fill each center with about 1 tablespoon of mini candies. 
- Replace the cut-out piece on top to cover the filling. 
- Make the frosting: Beat butter until creamy. Add powdered sugar gradually, then vanilla, salt, and milk until desired consistency. 
- Frost cupcakes and decorate with sprinkles or additional candy as desired.