Preheat oven to 350°F. Line two cookie sheets with Silpats or parchment paper.

Mix peanut butter, egg, sugars, and baking soda in a large bowl. You can use a mixer, but it's easy to do by hand. Once incorporated, stir in Reese’s Pieces and peanut butter cups.

Scoop balls of cookie dough onto your prepared cookie sheets. We used a 2 tablespoon cookie scoop for this step. Use the tines of a fork to gently flatten each cookie.

Bake for 8 minutes. Cool before removing from cookie sheets. Note: these cookies can be crumbly so be careful when picking them up or packing them in lunches.