Brown the butter by placing it in a saucepan over medium heat. Stir until it melts, foams, and turns golden brown with a nutty aroma. Pour into a bowl and let it cool to room temperature.

In a large mixing bowl, combine granulated sugar, brown sugar, and the cooled browned butter. Whisk until smooth and fully blended.

Crack in the egg and whisk until the mixture becomes creamy and glossy.

Add baking powder, baking soda, and all-purpose flour. Gently fold with a spatula until just combined.

Pour in mini M&Ms and flat chocolate chip disks. Mix gently until they are evenly distributed throughout the dough.

Scoop the dough into evenly sized balls and shape them. Press extra mini M&Ms and chocolate chips on top to decorate.

Place the shaped cookie dough balls in the fridge for 30 minutes to firm up.

Preheat the oven to 190°C (375°F). Bake the cookies for 10 minutes or until the edges are golden and the centers still look slightly soft.

Immediately after baking, place a cookie cutter or metal round object over each cookie and swirl to make them perfectly round.

Allow the cookies to cool slightly on the tray before transferring to a cooling rack. Enjoy warm or store in an airtight container.