In a stand mixer, combine the butter and the peanut butter, mix until incorporated.
Gradually add the brown and white sugar until thoroughly mixed.
Mix in the eggs one at a time.
In a second mixing bowl, whisk the flour, cornstarch, salt and baking soda until combined.
Transfer the flour mixture into the peanut butter mixture while mixing until combined. Scrape the sides of the bowl to ensure the mixture is homogeneous.
Add the chopped peanuts and the chocolate chips and mix until well distributed.
Cover the mixing bowl with film and refrigerate for two hours.
Preheat the oven to 410°F (210°C)
Use a 1/4 measuring cup to scoop the cookie dough and place it on a baking tray lined with parchment paper. Use your fingers to form small bundles. You should be able to arrange 8-10 cookies per baking sheet (leave enough space between cookies).
Bake for 8-10 minutes. Work in batches to bake 22-24 cookies.
Cool on a rack until manageable before serving. Enjoy!