Preheat your oven to 350°F (175°C) and grease and flour each mini bundt pan.

In a large bowl, whisk together the flour, baking powder, salt, and granulated sugar.

In another bowl, beat the butter until light and fluffy, then gradually add sugar and mix well.

Add the eggs one at a time, then incorporate the milk and vanilla, mixing until smooth.

Gradually fold the dry mixture into the wet ingredients until just combined.

Fill each bundt pan a third full with batter, add candy fillings, then top with additional batter.

Bake for approximately 25 minutes, or until a toothpick comes out clean.

Allow cakes to cool for 10 minutes in the pans before inverting onto a wire rack. Mix powdered sugar with milk and drizzle over the cooled cakes.