How to Make It
In a bowl, whisk together the flour, baking powder, and salt. Set aside.
In a mixer, cream together the butter, brown sugar, and sugar until light and fluffy, about 2 minutes. Beat in the peanut butter until combined. Beat in the eggs and vanilla. Stir in the flour mixture until just combined. Stir in the M&M’s, reserving a handful to decorate the top of the cookies. Cover and chill the dough for at least 1 hour.
Preheat the oven to 375°F. Line a couple sheet pans with parchment paper. Form the dough into 1 1/2-inch balls using a 1-ounce cookie scoop and place on the lined sheet pan 2-inches apart. Lightly press the reserved M&M’s into the dough balls.
Bake for 11-14 minutes or until the cookies are just set on the edges and lightly browned. Let them cool for a few minutes and then transfer to a wire rack to finish cooling.