Beat room temperature butter with an electric hand mixer in a large bowl. Then add dark brown and white sugars and beat for about 3 minutes, or until light and fluffy. Then, beat in two large eggs, one egg yolk, and vanilla extract. Next, beat in crunchy peanut butter.
Then, add about half of the flour and the baking soda, and beat until just combined. Add remaining flour, beating until just combined. Stir in six ounces mini semisweet chocolate chips and one package of Reese's Peanut Butter Cups Minis Unwrapped.
Line a half sheet pan with parchment paper. I used my half sheet pan with lid3. Then, use a 2-oz ice cream scoop to portion the dough into 24 balls.
Roll the dough balls between gloved hands and flatten slightly. Place three Reese's Peanut Butter Cups Minis Unwrapped and 10 mini semisweet chocolate chips on top of each dough ball. Cover the pan and refrigerate for at least 12 hours, or overnight.
When you're ready to bake the cookies, preheat your oven to 350°F.
Line three half-sheet pans with parchment paper. Place eight refrigerated dough disks, about two inches apart, onto one of the prepared pans. Then, bake for 15-18 minutes. Repeat with the other two pans and the rest of the dough, baking the pans one at a time and leaving the unused dough in the refrigerator between bakes.
Remove the pan from the oven and let the cookies cool on the pan for 15 minutes. Transfer the cookies to a wire cooling rack to cool completely. Store in an airtight container for up to a week.
Yield 24 cookies
Tips/Notes
Make sure to check the ounces on the package; some only contain seven ounces. I used Plugra for this recipe.
Jif is my preferred brand.
If you don't have a half sheet pan with a lid, you can use a regular sheet pan. You'll need to place a piece of parchment on top of the dough, then cover the entire pan with plastic wrap.