Preheat your oven to 350°F (175°C). This ensures your cookies bake evenly and rise perfectly.
In a medium bowl, whisk together the all-purpose flour, cocoa powder, baking powder, baking soda, and salt. Set this mixture aside.
In a large mixing bowl, use an electric mixer to cream together the room temperature unsalted butter, creamy peanut butter, light brown sugar, and granulated sugar until the mixture is light and fluffy. This should take about 2-3 minutes.
Add the eggs, one at a time, mixing well after each addition. Then, blend in the vanilla extract until fully incorporated.
Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Be careful not to overmix.
Using a spatula or wooden spoon, gently fold in the semisweet chocolate chips and peanuts until evenly distributed throughout the dough.
Using a cookie scoop or tablespoon, drop rounded balls of dough onto a parchment-lined baking sheet, spacing them about 2 inches apart. Sprinkle a pinch of coarse salt on top of each cookie.
Bake the cookies in the preheated oven for 10-12 minutes, or until the edges are set but the centers are still soft. Remove from the oven and let them cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.