01 - Preheat oven to 325°F (165°C). Lightly spray an 8x8-inch baking pan with baking spray and line with parchment paper or foil.
02 - In a microwave-safe bowl, melt the butter and chopped chocolate in 30-second intervals, stirring between each, until smooth.
03 - Stir in the granulated and brown sugars until well blended. Whisk in the eggs and vanilla until the mixture becomes glossy.
04 - Fold in cocoa powder, flour, and salt with a silicone spatula until just combined.
05 - Gently fold in ½ cup of the Cadbury Mini Eggs.
06 - Spread the batter evenly into the prepared pan.
07 - Roughly chop the remaining ¼ cup of Mini Eggs and sprinkle on top.
08 - Bake for 40–45 minutes. Begin checking at 40 minutes — brownies are done when a toothpick inserted comes out with moist crumbs but no wet batter.
09 - Cool completely in the pan on a wire rack for 2 hours before slicing into squares.