Preheat oven to 350 and line a 9-inch square baking tray with parchment paper
Make the Brownie
Whip eggs and sugar until light and thick, like custard.
3 Eggs, 1 ¼ cups Granulated Sugar
Melt butter and chocolate together in the microwave at 30-second intervals.
1 ½ sticks Butter, 10.5 oz Dark Chocolate
Pour chocolate and butter mix into the egg/sugar mix and mix until combined.
Fold in flour and salt until combined.
1 cup All-purpose Flour, ½ teaspoon Salt
Set aside a small amount of the brownie batter for swirling on top (about ½ a cup, or more if you want more brownie on top) then pour the rest of the batter into the prepared pan.
Make the Cheesecake
Place all the cheesecake ingredients in a bowl and cream together until smooth.
13 oz Cream Cheese, 1 ½ cups Powdered Sugar, ½ teaspoon Vanilla Extract, 2 Eggs
Pour on top of the brownie mix in the pan, and use a toothpick or knife to swirl the two layers together just slightly - just so they bake together well. Add a few dollops of the reserved brownie mix on top and swirl those into the top of the cheesecake to make a pretty design.
Bake for 30 - 35 minutes or until the cheesecake just starts to turn golden at the edges. there should still be a wobble in the middle of the cheesecake.
Let cool COMPLETELY before attempting to slice - seriously.
Notes
The quality of the chocolate really matters in this recipe and. you'll be able to taste the difference, so try to use a high-quality dark chocolate with at least 70% cocoa solids. For best results when slicing the cheesecake brownies, chill them in the fridge for an hour or so before slicing, then use a warmed knife to get super clean cuts - cleaning it off in between each slice.