In the bowl of a stand mixer cream together butter and peanut butter until smooth. Add in vanilla and mix well.
Add in flour and powdered sugar and mix on low to medium speed until dough forms a ball. Fold in peanut brittle bits.
Using a 2 oz cookie scoop scoop dough onto a lined baking tray and flatten slightly with the palm of your hand. Make an indentation in the center of the cookie with your thumb, creating a 1" circle.
Bake at 350 degrees for 13-15 minutes. Allow cookies to cool on the pan for 5 minutes before transferring to a flat surface to cool completely.
Once cook, spoon about 1 Tbs of caramel sauce into the center well of each cookie. Top with crushed peanuts if desired.