Line an 8 × 8-inch square baking pan with parchment paper or aluminum foil, leaving an overhang on two sides for easy removal after the fudge has set.

Reserve about 9 Cadbury Mini Eggs to keep whole. Roughly chop the remaining mini eggs into small and medium pieces for the topping, then set them aside.

In a medium saucepan over low to medium heat, combine the semi-sweet chocolate chips, half of the sweetened condensed milk, and the marshmallow creme. Stir constantly until the mixture is completely melted and silky smooth.

Pour the chocolate mixture into the prepared pan and spread it into an even layer using a spatula. Set aside while preparing the second layer.

In another saucepan, combine the white chocolate chips, the remaining sweetened condensed milk, and the marshmallow creme. Heat gently, stirring continuously until smooth. Remove from the heat and mix in the vanilla extract.

Carefully fold in the ⅓ cup of Easter sprinkles with just a few gentle strokes. Avoid overmixing so the colors stay vibrant instead of blending into the fudge.

Spread the white chocolate mixture evenly over the chocolate layer.

Sprinkle the remaining tablespoon of sprinkles across the top. Arrange the whole Cadbury Mini Eggs evenly over the surface, then scatter the chopped mini eggs around them for extra crunch and color.

Cover the pan and refrigerate for at least 4 hours, or leave it at cool room temperature overnight, until the fudge is completely firm.

Once set, lift the fudge out of the pan using the parchment or foil overhang. Peel away the lining and place the fudge on a cutting board.

Using a sharp knife, cut the fudge into 1-inch squares. If it's very cold from the refrigerator, let it sit at room temperature for 15–20 minutes before slicing for cleaner cuts.

Serve immediately or store in an airtight container in the refrigerator for up to one week.