In a small microwave safe mixing bowl, melt together the butter and chocolate chips in 30 second intervals, stirring in between each interval.
Once the mixture is melted and smooth, whisk in the cocoa powder.
To another mixing bowl add the egg, remaining whisked egg, and sugar. Vigorously whisk together the eggs and sugar until the mixture is pale and fluffy.
Add in the red food dye, stirring gently until well combined. If desired, add in some more for a deeper red color.
Add the melted chocolate mixture and mix until well combined.
Add in the flour and salt. Use a rubber spatula to lightly fold the flour into the mixture just until the last streak of flour disappears.
Pour the brownie batter into the loaf pan, reserving ~2-3 tbsp. for swirling on top.
Pour the cheesecake into an even layer on top of the brownie batter. Dollop the reserved brownie batter on top of the cheesecake layer, then use a knife to gently swirl the batter into the cheesecake.
Bake for 35-40 minutes, until the cheesecake only slightly wobbles in the center and has started to brown on the edges. (You can also check for doneness with a thermometer: it should read at least 180F/82C)
Wait for the brownies to fully cool before cutting. Serve, and enjoy!