Preheat oven to 375 degrees. Line a baking sheet pan with parchment or a baking mat, set aside.

In a food processor or blender, add 1 cup of the oats, cornstarch, baking powder and salt, pulse until the oats are finely ground but not completely powdered.

In the bowl of a stand mixer, or in a large mixing bowl with a hand mixer, beat the peanut butter and sugar. Add the egg and vanilla, mixing until combined. With mixing speed on low, gradually add the oat mixture and the remaining oats, mix just until combined. Stir in the chocolate chips with a spoon or use your hands to fully incorporate chips. Alternatively, just press chips into the tops of the cookies before baking.

Roll about a tablespoon of dough into a ball and then flatten slightly and place cookie onto prepared baking sheet. Place in the oven and bake for about 10 minutes. Remove from the oven and allow to cool for 5 minutes on the pan before transferring to a wire racks to cool completely. Enjoy!