• Preheat oven to 350°F
• Combine butter and chocolate chips in saucepan over medium heat until melted together. Transfer to a large bowl.
• Add cocoa powder, and sugars and stir until completely combined.
• Add eggs and egg yolk, one at a time, stirring well after each addition.
• Add vanilla extract and salt and stir to combine.
• Add flour and stir until completely combined.
• Reserve 1/4 cup of the batter and spread the rest of the batter evenly into prepared 8x8 pan. Prepare your cheesecake topping.

For the Cheesecake:

• Combine cream cheese and sugar in a medium-sized bowl. Use an electric mixer to beat until creamy.
• Stir in egg and vanilla extract. Stir until well-combined.
• Pour cheesecake over prepared brownie batter. Take your reserved 1/4 cup brownie batter and drop/drizzle over cheesecake.
• Use a knife to swirl brownie batter and cheesecake together.
• Bake on 350°F for 25-30 minutes or until center is set and a toothpick inserted in the center comes out mostly clean with a few fudgy crumbs.
• Allow to cool COMPLETELY before cutting and serving.
• Will last for 5 days covered in the fridge.