Preheat your oven to 445°F (230°C) and line a 6-inch round cake pan with parchment paper.

In a large mixing bowl, beat softened cream cheese until smooth. Gradually add castor sugar and vanilla, whisking until fluffy.

Add eggs one at a time, whisking thoroughly after each addition until smooth and glossy.

Fold in melted dark chocolate until fully combined.

Sift cocoa powder and cornstarch over the batter, gently stirring to combine.

Pour in the heavy whipping cream and whisk until homogeneous.

Pour the batter into your prepared cake pan and tap gently to release air bubbles.

Bake for about 25 minutes, until the top is golden brown and the center is slightly jiggly.

Cool at room temperature for at least an hour, then refrigerate uncovered for 4 hours.

Let sit at room temperature for 30 minutes before serving, or serve cold.