In a medium bowl, combine peanut butter, powdered sugar, a pinch of salt, vanilla extract, and whole milk. Mix until smooth and well-blended. Set aside.

Preheat your oven to 350°F (175°C) and prepare a baking sheet with parchment paper.

In a large bowl, whisk together all-purpose flour, unsweetened cocoa powder, black cocoa powder, and pudding mix. Add baking soda and salt.

Cream together softened butter and granulated sugar until light and fluffy. Add eggs one at a time, mixing until well combined.

Gradually add dry ingredients to the creamed mixture, mixing on low speed. Fold in Reese's Pieces and peanut butter chips.

Scoop about 4 ounces of dough, flatten slightly, place peanut butter filling in center, and fold dough around it. Roll into a ball.

Bake cookies for 10-12 minutes until edges are set and centers slightly underbaked. Remove from oven.

Cool cookies on the baking sheet for 15 minutes before transferring to a wire rack to cool completely.