Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the softened unsalted butter, creamy peanut butter, and light brown sugar. Use an electric mixer to cream these ingredients together until smooth and fluffy, about 2-3 minutes.
Add the large egg and vanilla extract to the mixture. Beat until well combined.
In a separate bowl, whisk together the all-purpose flour, baking powder, and a pinch of salt. Gradually add the dry ingredients to the wet mixture, mixing until just combined.
Gently fold in the mini peanut butter cups and peanut butter chips.
Using a cookie scoop or tablespoon, drop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Place the baking sheet in the preheated oven and bake for 10-12 minutes, or until the edges are lightly golden.
Remove the cookies from the oven and let them cool on the baking sheet for about 5 minutes. Then, transfer them to a cooling rack to cool completely.
