01 - Preheat oven to 350°F. Line an 8x8-inch baking pan with parchment paper, allowing overhang on sides for easy removal later.
02 - Whisk together flour, baking powder, and salt in a medium bowl. Set aside for later use.
03 - In a large mixing bowl, combine melted butter and brown sugar. Stir until smooth and well blended.
04 - Beat in the egg and vanilla extract until fully incorporated into the butter mixture.
05 - Gently fold dry ingredients into wet mixture using a spatula. Mix only until just combined—avoid overmixing to prevent tough texture.
06 - Add white chocolate chips, milk chocolate chips, and chopped Cadbury Mini Eggs. Fold gently to distribute evenly throughout batter.
07 - Spread batter evenly into prepared pan. Press reserved whole Mini Eggs onto surface, lightly embedding them into batter.
08 - Bake for 22-25 minutes until top is golden brown and a toothpick inserted in center comes out with a few moist crumbs.
09 - Let blondies cool completely in pan. Using parchment overhang, lift out and cut into 12 equal squares.