Prepare the Strawberry Sauce:

• In a medium saucepan, combine the strawberries, granulated sugar, and lemon juice over medium heat. Stir occasionally and cook until the strawberries soften and break down (about 5-7 minutes).
• Mix the cornstarch with water to form a slurry, then add it to the strawberry mixture. Stir until the sauce thickens (about 1-2 minutes).
• Remove from heat and allow the sauce to cool to room temperature.

Prepare the Crust:

• Preheat the oven to 325ºF (163ºC).
• In a medium bowl, combine the graham cracker crumbs, sugar, and melted butter. Stir until the crumbs are well coated.
• Press the mixture into the bottom of a 9-inch springform pan to form an even crust. Bake for 8-10 minutes or until golden. Remove from the oven and allow to cool while preparing the cheesecake filling.

Prepare the Cheesecake Filling:

• In a large bowl, beat the softened cream cheese and sugar until smooth and creamy.
• Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.
• Add the sour cream and heavy cream, and mix until the filling is smooth and well combined.

Assemble the Cheesecake:

• Pour the cheesecake filling over the cooled crust in the springform pan.
• Spoon the cooled strawberry sauce in small dollops over the cheesecake filling.
• Use a knife or skewer to swirl the strawberry sauce into the filling, creating a marbled effect.

Bake the Cheesecake:

• Bake at 325ºF (163ºC) for 50-60 minutes or until the center is set but still slightly jiggly.
• Turn off the oven, crack the oven door slightly, and let the cheesecake cool in the oven for 1 hour. This helps prevent cracking.

Chill and Serve:

• After the cheesecake has cooled to room temperature, cover it and refrigerate for at least 4 hours, or overnight, to set.
• Before serving, remove the cheesecake from the springform pan and transfer it to a serving plate.
• Garnish with extra fresh strawberries if desired and serve.