Preheat oven to 350 degrees F.
Grease a baking sheet with nonstick cooking spray or line a baking pan with parchment paper and set aside.
In a large bowl, mix the flour, baking soda, salt, and baking powder. Set aside.
In the bowl of a stand mixer, add the butter and sugars and cream together using the paddle attachment until light and fluffy—about 3 minutes.
Add the eggs slowly along with the vanilla, mixing on low to combine.
Add the dry ingredients to the wet ingredients and mix on low speed until almost completely combined. Add the chocolate chips (reserving a handful) and mix on low until the butter has mixed in and the flour is no longer dry.
Scoop the cookie dough into balls that are about 2-3 tablespoons. Lightly press an unwrapped peanut butter cup into the center of each dough ball, then cover the entire peanut butter cup with the cookie dough.
Place the cookies about 2" apart on your reserved cookie sheets.
Bake in your preheated oven for about 8-10 minutes. Take them out when they are just BARELY starting set in the middle of the cookie--no longer doughy.
As soon as you remove the cookies, sprinkle the rest of the chocolate chips over the top along with the chopped peanuts. Let them sit on the baking pan to cool for 2 minutes before removing to a wire cooling rack. Enjoy!