01 -
Preheat the oven to 325°F. Line the bottom of a 9-inch springform pan with parchment paper and lightly grease the sides to ensure easy removal.
02 -
Melt the butter and let it cool slightly. Whisk in sugar, then add eggs individually, mixing well after each. Stir in vanilla. Sift cocoa powder, flour, salt, and baking powder, then fold until just combined. Pour batter into pan and bake for 18 to 22 minutes until just set but slightly underbaked. Remove and cool.
03 -
Beat cream cheese until smooth. Gradually add sugar and beat thoroughly. Add eggs one at a time on low speed. Incorporate sour cream, vanilla, and cornstarch, then beat gently until smooth, avoiding overmixing to prevent cracking.
04 -
Pour cheesecake filling over cooled brownie base and smooth the top. Place pan on a baking sheet and bake at 325°F for 45 to 50 minutes until edges are set and center slightly wobbly. Turn off oven, crack door, and cool inside for 1 hour to prevent cracks.
05 -
Remove from oven and cool to room temperature. Cover and refrigerate for 4 to 6 hours or overnight to set the layers properly and enable clean slicing.
06 -
Heat heavy cream until steaming. Remove from heat; add chocolate chips, butter, and corn syrup. Let rest for 2 minutes, then stir until smooth. Stir in vanilla and let cool slightly before using.
07 -
Release cheesecake from pan. Pour hot fudge sauce evenly over the top. Pipe or spoon whipped cream around the edges and garnish with cherries, sprinkles, and chopped nuts as desired.