Preheat the oven to 350°F. Spray a 8X8-inch pan with baking nonstick spray. Line the bottom and 2 sides with parchment paper and spray again. Set aside.
Using a mixer, beat the butter, brown sugar, and sugar for 2 minutes on high speed until fluffy. Add in the peanut butter and vanilla and beat again on medium-high speed for 1 minute.
½ cup Unsalted butter, ¾ cup Brown sugar, ⅛ cup White granulated sugar, ½ cup Peanut butter, 1 teaspoon Pure vanilla extract
Add in the eggs and mix on medium until fluffy. Add in the flour, baking soda, and salt and mix on low speed until just combined.
1 Large egg, 1 ¼ cup All-purpose flour, ¼ teaspoon Baking soda, ½ teaspoon Salt
Fold in the chocolate chips and chopped Nutter Butters. Pour the cookie dough into the pan and flatten it until even.
¾ cup Semi-sweet chocolate chips, 1 cup Chopped Nutter Butters
Bake for 20-28 minutes. Bake until it is golden on top. Immediately top with extra Nutter Butters and chocolate chips. Cool completely on a cooling rack. Then, remove the bars from the pan and cut into squares.