01 -  Preheat your oven to 350°F (175°C). Line an 8-inch (20 cm) square baking pan with parchment paper, leaving an overhang for easy removal. 
 02 -  In a large bowl, whisk together melted butter and sugar until smooth. Add eggs, vanilla, and red food coloring, and whisk until combined. 
 03 -  Sift in flour, cocoa powder, and salt. Stir gently just until incorporated—do not overmix. 
 04 -  Reserve 1/4 cup of the red velvet batter and set aside. Pour the remaining batter into the prepared pan and spread evenly. 
 05 -  In a separate bowl, beat cream cheese, sugar, egg, and vanilla until smooth and creamy. 
 06 -  Dollop the cheesecake mixture over the brownie batter in the pan. Add spoonfuls of the reserved red velvet batter on top. 
 07 -  Using a knife or skewer, gently swirl the batters together to create a marbled effect. 
 08 -  Bake for 33–36 minutes, or until the center is set and a toothpick inserted comes out with a few moist crumbs. 
 09 -  Cool completely in the pan, then lift out using the parchment. Cut into 16 squares.