Preheat the oven to 350 F. Line a 12 cup muffin pan with paper liners. In a large bowl, whisk together flour, sugar, cocoa powder, salt, and baking soda. Add in eggs, melted butter, and vanilla extract. Mix until smooth.
In a medium bowl, whisk together flour, salt, and baking soda. In a large bowl, combine butter with peanut butter and granulated sugar until fluffy. Add in egg and vanilla extract, and mix until smooth. Add in the flour mixture, mix until it is fully combined.
Fold in sprinkles and chocolate chips. Evenly divide the brownie batter between the prepared muffin pan. Top with the cookie dough. Bake for 20-25 minutes.