Line two baking sheets with parchment paper. Set aside.

Place the 2 tablespoons of granulated sugar in a small bowl. Set aside.

In a large bowl, beat the butter, granulated sugar, and light brown sugar together until light and fluffy.

Add in the egg and beat until combined. Scrape down the sides of the bowl.

Add in the peanut butter, baking soda, and salt and beat until fully incorporated. Add in the flour and beat on low speed until combined.

Shape the dough into 1-inch balls and roll in the granulated sugar.

Place the dough balls 2 inches apart on the prepared baking sheets. Gently flatten the cookies with the heel of your palm. Place the baking sheets in the refrigerator to chill for 30 minutes.

Preheat the oven to 350 F.

Bake the cookies for the 12-14 minutes or until they’re a lightly golden brown. Let the cookies cool for 2 minutes on the baking sheets before transferring to a wire rack to cool completely.

In a large bowl, beat the peanut butter and butter together until creamy.

Gradually add in the powdered sugar and salt and beat until combined and the mixture has slightly thickened. Add in the vanilla and milk and beat until the frosting is thick and spreadable.

Use an offset spatula to frost the tops of the cookies. Sprinkle the tops of the cookies with the M&M’S minis.