Preheat oven to 350 degrees.
In a medium bowl, whisk together flour, baking powder, baking soda, and salt.
In the bowl of stand mixer (or with a hand mixer), cream together butter, white sugar, light brown sugar, and vanilla extract on medium speed for about 1 minute.
Scrape down the sides of your bowl.
Add egg and mix on medium/low speed until just incorporated.
Add the flour mixture to the butter mixture.
Mix on low until just incorporated. Do not over-mix!
Fold in ¾ cup M&Ms with a spatula.
Add 2 tablespoons of dough, about an inch apart, on a greased baking sheet.
Bake at 350 degrees for 8-10 minutes until cookies are just set. Don’t over-bake!
Right out of the oven, press 3-4 M&Ms on top of each cookie.
Let cookies rest on the baking sheet for 10 minutes before serving or transferring to a wire rack.
