Step 1

Preheat oven to 350°F. Line a 9-inch square baking pan with parchment paper so that the paper overhangs by about 2 inches on opposite sides. Spray the paper with nonstick baking spray.

Step 2

Place the chocolate and butter in a microwave-safe bowl. Heat in the microwave at half-power in 30-second increments until the butter has melted and the chocolate melts when stirred. Stir until smooth. Set aside to cool slightly.

Step 3

Combine the sugar, brown sugar, eggs, vanilla, and salt in a large bowl. Add the cooled chocolate, and mix until combined.

Step 4

Add the flour, and mix just until combined.

Step 5

Transfer the batter to the prepared pan, and spread evenly. Set aside.

Step 6

Using an electric mixer on medium speed, beat the cream cheese, sugar, vanilla, and egg until thoroughly combined and smooth. Add the cookie butter and mix until combined.

Step 7

Drop the cheesecake mixture by small amounts over the top of the brownie batter. Use an offset spatula or thin knife to swirl into the brownie batter.

Step 8

Bake 40 to 45 minutes, or until a pick inserted into the center comes out clean.

Step 9

Cool the brownies completely in the pan on a wire rack. Then cover and refrigerate at least 4 hours before cutting into bars.

Step 10

To cut into bars, use the overhanging parchment paper to transfer the brownies to a cutting board. Use a sharp knife to cut into bars.