1. Line a cookie sheet with parchment paper and set aside. Preheat oven to 350 degrees F. 2. In a large bowl, whisk together butter, both sugars and eggs until creamy. 3. Add peanut butter, oats, flour and baking powder. Mix together until all ingredients are well-combined. 4. Add Reese’s Pieces and carefully fold into batter. 5. Use an ice cream scoop to drop cookie batter onto the lined cookie sheet, about 2 inches apart from each other. 6. Bake for 10-13 minutes and allow to cool before serving. Enjoy!