Ingredients (12 large cookies)

155g (11 Tbsp) unsalted butter, melted

150g (3/4 cup) brown sugar, packed

150g (3/4 cup) granulated sugar

1 large egg, room temperature

2 1/2 tsp vanilla extract

1/2 tsp baking soda

3/4 tsp baking powder

1/2 tsp fine sea salt

200g (1 2/3 cups) all-purpose flour

50g (1/2 cup) dark or Dutch-processed cocoa powder

85g (scant 1/2 cup) mini chocolate chips

90g (scant 1/2 cup) M&Ms, plus more for the tops

Mix and Chill the Dough

In a large bowl, melt the butter in the microwave. Let it cool for about 5 minutes – it should be warm, not hot. Whisk in the brown sugar and granulated sugar until fully combined.

Add the egg and vanilla extract and whisk until the mixture is smooth and slightly glossy. Add the baking soda, baking powder, and salt, and whisk them in.

Switch to a spatula and fold in the all-purpose flour and cocoa powder. Mix until there are just a few streaks of flour left. Add the mini chocolate chips and M&Ms and fold until the dough comes together. The dough will be thick and sticky.

Cover the bowl tightly and chill the dough in the refrigerator for at least two hours. Do not skip this step.

Bake the Cookies at 350F for ~11-13 Minutes

Preheat the oven to 350F and line a baking sheet with parchment paper.

Scoop the dough into large balls, about 1/4 cup or 75 grams each. Space them 2-3 inches apart on the baking sheet. If you want, you can press a few extra M&Ms onto the tops of the dough balls before baking.

Bake for ~11-13 minutes. The edges of the cookies should look set, but the centers will be puffy and soft. Let them cool on the baking sheet for at least 5 minutes, as they will firm up as they cool. After 5 minutes, you can transfer them to a wire rack.