Preheat oven to 350°F (175°C). Line a baking sheet with parchment.

Cream peanut butter, butter, and brown sugar until smooth. Beat in egg and vanilla.

Whisk flour, baking soda, and salt; stir into wet mixture. Fold in oats, chopped peanuts, and chips.

Scoop tablespoon-sized balls onto sheet, flatten slightly with a fork. Bake 9–11 minutes until edges set.

Cool on pan 5 minutes, then transfer to a rack to finish cooling.