Preheat the oven to 350°F.
Beat the butter in a large bowl until creamy and fluffy, about 2 minutes.
Add peanut butter and both sugars to the butter, beating for 2–3 minutes.
Mix in the vanilla pudding mix for 1 minute.
Add eggs and vanilla extract; beat for another 2 minutes.
In a separate bowl, combine flour, baking soda, and salt.
Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Fold in mini chocolate chips and chopped Reese’s peanut butter cups.
Scoop dough using a cookie scoop onto a prepared cookie sheet, spacing about 2 inches apart.
Bake for about 10 minutes, taking care not to overbake.