Preheat oven to 350Prepare a 9"x13" baking dish by spraying with cooking spray or lining with parchment paper.

In a large microwave-safe bowl, add chocolate and butter and microwave 30 seconds at a time, stirring after each increment, until butter and chocolate are melted and smooth.

Add sugar and stir until combined. Add eggs, salt, and vanilla and cocoa powder and combine.

Add flour and carefully fold in until flour is combined completely.

Spoon brownie batter into baking dish and spread until evenly distributed.

Add spoonfulls of cookie butter on top of the batter. Using a skewer or fork, swirl the cookie butter into the brownie batter until there are cookie butter swirls all over the batter.

Bake for 28-35 minutes, or until a skewer inserted into the brownies comes out clean. Let cool, and enjoy!