Prep your pan: Heat the oven to 350°F (175°C). Line a 9x13-inch metal baking pan with parchment, leaving an overhang for easy lifting. Lightly grease the parchment.

Chop the Mini Eggs: Place them in a zip-top bag. Use a rolling pin to gently crack them. Aim for halves and big chunks. Avoid turning them into dust.

Melt the butter: In a medium saucepan over low heat, melt the butter. Remove from heat and let it cool for 3–5 minutes so it’s warm, not hot.

Whisk in sugars: Add granulated and brown sugar to the warm butter. Whisk until glossy and combined. This helps that shiny, crackly top.

Add eggs and vanilla: Whisk in the eggs one at a time, mixing well after each. Stir in the vanilla. The batter should look thick and smooth.

Mix dry ingredients: In a separate bowl, whisk cocoa powder, flour, salt, and baking powder to break up any lumps.

Combine: Fold the dry ingredients into the wet until just combined. Don’t overmix. If using chocolate chips, fold them in now.

Stir in the candy: Gently fold in about 1 cup of the chopped Mini Eggs. Reserve the rest for the top.

Spread and top: Pour batter into the pan and smooth the surface. Sprinkle the remaining Mini Egg pieces evenly over the top. Press them in lightly so they stick.

Bake: Bake for 24–28 minutes, until the edges are set and a toothpick in the center comes out with moist crumbs, not wet batter. Slight underbaking keeps them fudgy.

Cool completely: Set the pan on a rack and cool for at least 1 hour. For the cleanest slices, cool to room temp, then chill for 30 minutes.

Finish and slice: Sprinkle with a pinch of flaky sea salt if you like. Lift out using the parchment, and cut into 16–24 squares with a sharp knife, wiping the blade between cuts.