Preheat the oven to 350°F (180°C). Line a 9-inch springform pan with parchment paper and wrap the outside with aluminum foil.

Melt the bittersweet chocolate and butter together in the microwave, stirring every 30 seconds until smooth. Cool slightly.

Beat the sugar, eggs, and vanilla until pale and frothy.

Slowly pour in the melted chocolate mixture while mixing.

Fold in the flour, cocoa powder, and salt until just combined.

Spread the batter evenly into the prepared pan.

Bake for 25–30 minutes or until a toothpick comes out mostly clean.

Cool completely before adding the cheesecake layer.

Lower the oven temperature to 325°F (165°C).

Place a pan of warm water on the bottom oven rack to create steam.

Melt the chocolate chips and allow them to cool slightly.

Beat the cream cheese and sugar until completely smooth.

Mix in the melted chocolate, vanilla, cocoa powder, and salt.

Blend in the sour cream.

Add the eggs one at a time, mixing gently after each addition.

Pour the filling over the cooled brownie crust.

Bake the Cosmic Brownie Cheesecake for 60–70 minutes, until the edges are set and the center still has a slight jiggle.

Turn off the oven, crack the door open, and allow the cheesecake to cool inside for one hour.

Cool at room temperature for another hour before refrigerating overnight.

Place the chocolate chips into a bowl.

Heat the heavy cream until steaming but not boiling.

Pour over the chocolate.

Let stand for one minute before whisking until smooth.

Chill for about one hour until slightly thickened.

Remove the chilled cheesecake from the springform pan.

Spread the ganache evenly across the top.

Decorate with candy-coated chocolate pieces.

Slice using a warm knife for clean, beautiful slices.