Preheat oven to 350°F (175°C). Line baking sheets with parchment paper or silicone liners.
Whisk together the flour, baking powder, baking soda, and salt. Set aside.
Using an electric mixer on medium speed, beat the butter, peanut butter, sugar, and brown sugar until light and fluffy. Add the egg and vanilla, and mix well.
Reduce mixer speed to low. Gradually add the flour mixture, mixing just until combined.
Stir in the peanut butter chips, M&Ms, peanut butter cups, and peanuts.
Drop the dough by 3-tablespoon portions onto the prepared pans, leaving about 2 to 3 inches between the cookies. Flatten the top of each cookie slightly.
Bake 12 to 15 minutes, or until the edges are lightly browned.
Cool on the pan on a wire rack for 5 minutes. Then transfer the cookies to a wire rack to cool completely.
Notes
*As a general rule, I don't recommend using natural peanut butters for baking.
**The weight measurement is just a ballpark. I quarter about 8 of the standard miniature peanut butter cups. There are smaller ones available that wouldn't need chopping.