1. Prepare the Brownie Base

1. Preheat oven to 350°F (175°C). Grease and line a 9-inch springform pan with parchment paper.
2. In a bowl, whisk together melted butter and sugar.
3. Add eggs and vanilla extract, mixing until smooth.
4. Stir in flour, cocoa powder, salt, and baking powder until combined.
5. Pour the brownie batter into the prepared pan and bake for 15-18 minutes.
6. Remove from the oven and let it cool slightly while preparing the cheesecake layer.

2. Make the Cheesecake Filling

1. In a large bowl, beat cream cheese and sugar until smooth and creamy.
2. Add eggs, one at a time, mixing after each addition.
3. Stir in vanilla extract and sour cream until combined.
4. Pour the cheesecake batter over the cooled brownie layer.

3. Bake the Cheesecake

1. Reduce oven temperature to 325°F (160°C).
2. Bake for 45-50 minutes, until the edges are set but the center is slightly jiggly.
3. Turn off the oven and let the cheesecake cool inside with the door slightly open for 1 hour.
4. Refrigerate for at least 4 hours or overnight before adding the topping.

4. Make the Hot Fudge Topping

1. In a small saucepan, heat heavy cream over medium heat until warm (do not boil).
2. Remove from heat and stir in chocolate chips and butter until smooth.
3. Add powdered sugar and vanilla extract, whisking until glossy.
4. Let the fudge sauce cool slightly before pouring over the chilled cheesecake.

5. Assemble & Serve!

• Pour the hot fudge sauce evenly over the cheesecake.
• Garnish with whipped cream, chopped nuts, and maraschino cherries.
• Slice and serve chilled for the ultimate sundae-inspired dessert experience!