Preheat your oven to 350°F (175°C) and grease the 9x13 inch baking pan or line it with parchment paper for easy removal.
In a large mixing bowl, melt the unsalted butter. You can do this in the microwave or on the stovetop.
Once melted, add the granulated sugar to the butter and whisk until well combined.
Beat in the eggs, one at a time, mixing well after each addition. Add the vanilla extract and mix.
In a separate bowl, combine the all-purpose flour, cocoa powder, salt, and baking powder.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Be careful not to overmix.
Fold in the M&Ms gently, reserving some for the topping.
Pour the brownie batter into the prepared baking pan, spreading it evenly.
Sprinkle the reserved M&Ms on top of the brownie batter.
Bake in the preheated oven for about 25 minutes or until a toothpick inserted into the center comes out mostly clean (a few moist crumbs are okay).
Once baked, remove from the oven and let the brownies cool in the pan for at least 15 minutes before slicing into squares.
Enjoy your delicious Easter brownies filled with joy and sweetness!