Melt the unsalted butter and mix with granulated and brown sugar until smooth. Add eggs one at a time, mixing well after each. Stir in vanilla extract.
In a separate bowl, beat the softened cream cheese until smooth. Add powdered sugar and vanilla extract, mixing until creamy.
Pour half of the brownie batter into a greased springform pan. Spread evenly, then pour cheesecake filling over it. Sprinkle chocolate chips on top and cover with remaining brownie batter.
Preheat oven to 350°F. Bake for 45-50 minutes until a toothpick comes out with a few moist crumbs.
Cool in the pan for 10 minutes, then remove sides of the springform pan. Chill in the refrigerator for at least 120 minutes before serving.