Cheesecake Brownies

Preheat oven to 350°F. Line an 8-inch square baking pan with parchment paper, leaving a 1-inch overhang on 2 sides. Lightly coat with cooking spray.

Melt butter in a large saucepan over medium-low heat. Add 1 cup sugar and chocolate chips; whisk constantly just until the chocolate has melted and the mixture is mostly smooth, about 30 seconds. Remove from heat and stir in cocoa, 1 teaspoon vanilla and 1/2 teaspoon salt. Let cool, stirring occasionally, for 10 minutes. Whisk in 3 eggs, 1 at a time; stir until the batter is glossy and smooth. Transfer 1/3 cup batter to a small bowl and set aside. Gently fold 3/4 cup flour into the batter in the pot. 

Beat cream cheese with an electric mixer in a large bowl until smooth. Add the remaining 1/3 cup sugar, 1/4 cup flour, 1 teaspoon vanilla and pinch of salt; beat until smooth, scraping down the sides of the bowl as necessary. Add the remaining egg and beat again until smooth.

Spread the brownie batter evenly in the prepared baking pan, then top with the cream cheese batter, spreading evenly. Dollop the 1/3 cup reserved brownie batter onto the cream cheese layer. Using a toothpick or sharp knife, swirl the dolloped brownie batter into the cheesecake layer. 

Bake until a toothpick inserted in the center comes out clean, 30 to 35 minutes. Let cool completely, about an hour, before cutting and serving.