Crush the 8 Nutter Butter cookies in a food processor or blender. Remove 1/4 cup of crumbs and set aside for rolling. Preheat oven to 350 degrees. Use parchment paper or a silpat mat to line a baking sheet.
Cream the peanut butter, butter, sugar and brown sugar in a stand mixer until light and fluffy (about 2-3 minutes). Scrape the sides of the bowl to make sure all ingredients are blended.
Add in the egg and vanilla and beat until combined.
Add in flour, cornstarch, CRUSHED Nutter Butter Crumbs (that you blended in the food processor but NOT the 1/4 cup that you reserved for rolling), baking soda and salt. Mix until all combined.
Stir in the peanut butter chips and 8 CHOPPED Nutter Butter cookies.
Scoop out about 2 TBSPs of dough for smaller cookies (or 1/4 cup dough for even BIGGER cookies). Roll into balls. Roll dough balls in remaining 1/4 cup Nutter Butter crumbs. Place dough balls on prepared pan (12 cookies to a pan if small cookies and 6 to a pan if BIG cookies). Gently press down on each cookie to form a disc.
Bake for about 10-11 minutes. Remove from oven. Let cool on tray for 5 minutes. Transfer cookies to cooling rack. NOTE: Baking time will be longer if you make BIG cookies.
Microwave 1/2 cup peanut butter chips in microwave for 45 seconds or until melted. Stir. Transfer melted peanut butter chips into a Ziploc bag and cut off one corner of the bag. Drizzle peanut butter over each cookie.