Line a round baking tin with parchment paper, ensuring there is at least a 2-inch overhang above the rim. This will help achieve the rustic look characteristic of San Sebastian Cheesecake.

Preheat the oven to 220°C (425°F).

In a large mixing bowl, beat the cream cheese using a hand or stand mixer until smooth and lump-free.

Sift the granulated sugar into the cream cheese, then beat for approximately 3 minutes until the mixture is well-blended and creamy.

Crack the eggs in one at a time, mixing thoroughly after each addition to ensure complete incorporation.

Pour in the heavy cream and vanilla extract, and continue mixing until the batter is smooth and silky.

Sift the cornstarch into the mixture and stir until fully combined. Use a spatula to scrape the sides of the bowl and ensure the batter is homogeneous.

Pour the cheesecake batter into the prepared tin and tap it gently on a flat surface to release any trapped air bubbles.

Place the tin in the preheated oven and bake for 30–40 minutes. The top should develop a deep caramelized color, and the center will remain slightly jiggly. This is intentional, as the cheesecake will set while cooling.

Remove the cheesecake from the oven and allow it to cool completely in the tin. Once cooled, refrigerate for at least 2 hours, preferably overnight, to achieve the desired texture.