In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter. Stir until the mixture resembles wet sand.
Press the mixture firmly into the bottom of a 9-inch springform pan. Use the back of a spoon or a flat-bottomed glass to pack it down evenly.
Bake for 8-10 minutes, then set aside to cool.
Step 2: Make the Blueberry Swirl
In a saucepan over medium heat, combine blueberries, sugar, and lemon juice. Cook for about 5 minutes, stirring occasionally, until the berries start to break down.
Add the cornstarch-water mixture and stir continuously until the sauce thickens.
Remove from heat and let it cool to room temperature.
Step 3: Prepare the Cheesecake Filling
In a large bowl, beat the softened cream cheese until smooth and fluffy.
Add sugar and continue beating until well combined.
Mix in eggs one at a time, ensuring each egg is fully incorporated before adding the next.
Stir in vanilla extract, sour cream, and heavy cream, mixing until smooth and creamy.
Step 4: Assemble and Swirl
Pour the cheesecake batter over the cooled crust.
Drop spoonfuls of the blueberry sauce on top of the batter.
Use a toothpick or a knife to gently swirl the blueberry sauce into the cheesecake, creating a marbled effect.
Step 5: Bake the Cheesecake
Place the springform pan in a larger baking dish filled with 1 inch of hot water (this prevents cracks).
Bake for 50-60 minutes, or until the center is slightly jiggly but set around the edges.
Turn off the oven, crack the door open, and let the cheesecake cool inside for 1 hour to prevent sudden temperature changes.
Step 6: Chill and Serve
Transfer the cheesecake to the refrigerator and chill for at least 4 hours (overnight is best!).
Once fully set, remove from the springform pan and slice.