Preheat oven to 350 degrees. Grease a 10 or 12 inch cast iron skillet.

In a large bowl, combine melted butter, sugar, eggs, and vanilla. Mix until just combined. Add cocoa powder, flour, salt, and baking powder to bowl; mix to combine, but don’t over mix. Add the chocolate chips and almost all the chopped Cadbury mini eggs (leave about ¼ cup out, reserving for topping), to the batter, and fold to combine.

Pour batter into skillet and spread evenly. Sprinkle remaining chopped Mini Eggs on the top of the batter.

Place in oven and bake for 30-35 minutes. Check at 30 minutes with a toothpick and cook additional minutes if needed. Remove from oven.

Top with whipped cream. Slice and serve.