- the brownie batter into the cheesecake layer to achieve a marbled effect. (Be careful not to overmix; you want distinct layers that merge in a beautiful, messy way.)
- Return the pan to the oven and bake for 35–40 minutes. The bars are done when the edges are set and a toothpick inserted in the center comes out mostly clean (a few moist crumbs are okay).
- Remove from the oven and let the bars cool completely in the pan on a wire rack.
- Once cooled, refrigerate for at least 2 hours
