Preheat your oven to 350F (175C) and line a 9×9” (23x23cm) baking pan with parchment paper (use enough so that parchment is hanging over two sides of the pan.

Combine butter and chopped chocolate in a large, microwave safe bowl. Heat in 25-second intervals, stirring well in between, until both chocolate and butter are melted and mixture is smooth.

Immediately add cocoa powder and instant coffee (if using) and stir until combined.

Add sugars and stir well.

Add eggs and vanilla extract and stir very well.

Sprinkle salt and flour over the batter and stir until completely combined. Add chocolate chips, if using, and stir well.

Spread batter evenly into prepared pan (see note if you intend to do a chocolate brownie swirl on top) and transfer to 350F (175C) oven and bake for 13-15 minutes (the surface of the brownies should be beginning to set, but note that the brownies will not be cooked completely during this time!). While brownies are baking, prepare your cheesecake layer:

Cheesecake Layer: Cream together cream cheese and sugar until completely smooth and well combined (scrape sides and bottom of bowl to make sure there are no lumps hiding).

Stir in sour cream.

Add eggs and vanilla extract and stir until combined.

Once brownie batter is out of the oven, carefully and evenly pour cheesecake layer over the surface.

Return to 350F (175C) oven and bake another 25-28 minutes or until cheesecake is set (center will still be jiggly if jostled). Edges may be slightly puffed or even slightly golden brown.

Remove from oven and allow to cool at room temperature until no longer warm. Transfer to refrigerator and chill 3-4 hours before slicing and serving. If desired, drizzle sliced cheesecake brownies with additional melted chocolate chips before serving.