Step 1

Preheat the oven to 350°.

Step 2

Add the butter and cream cheese to a large bowl and beat for 2-3 minutes with an electric mixer. Add the egg, vanilla and peanut butter and mix for another 2-3 minutes. Add the sugars and mix for 2-3 more minutes.

Step 3

Add the flour, baking soda, baking powder, salt and cornstarch. Mix just until combined. With a wooden spoon or spatula, fold in the chocolate chips and Reese's pieces.

Step 4

Use a cookie scoop to scoop dough onto cookie sheets that are lined with parchment paper or silicone baking mats. At this point, I usually gently press a few more Reese's pieces on the top of the cookie dough so that the cookies look prettier when they are cooked.

Step 5

Bake for 12 minutes or until the edges just barely begin to brown. Let the cookies cool on the baking sheet for about 3-5 minutes before transferring to a wire rack to cool completely.