1. Preheat the Oven

Begin by preheating your oven to 325°F (163°C). This will ensure an even bake for your cheesecake bars.

2. Prepare the Graham Cracker Crust

In a small bowl, combine the graham cracker crumbs, melted butter, and sugar. Stir until all the crumbs are moistened, and the mixture starts to resemble wet sand. Once fully combined:

• Press the mixture firmly into the bottom and up the sides of a 9×13-inch glass baking dish.
• Bake for 10 minutes, then remove from the oven and let the crust cool while you prepare the filling.

3. Make the Cheesecake Filling

In a medium-sized bowl, beat the room-temperature cream cheese, sugar, and vanilla extract together. You’ll want to whip these ingredients until the mixture is light and fluffy, usually taking around 2-3 minutes.

• Add in the eggs one at a time, mixing on low speed after each addition. This ensures that the eggs are well incorporated without overbeating the mixture, which could affect the texture of the cheesecake.

Once the mixture is smooth and creamy, pour it over the cooled graham cracker crust, spreading it out evenly.

4. Prepare the Blackberry Sauce

In a small saucepan over medium heat, combine the blackberries, sugar, 2 tablespoons of water, and lemon juice. Stir continuously until the mixture thickens and the blackberries have softened, releasing their juices.

• Strain the mixture to remove the seeds, returning the liquid back to the pan.
• In a small bowl, mix the cornstarch and remaining tablespoon of water, then add it to the blackberry mixture.
• Continue cooking until the sauce thickens further. Remove from heat and let it cool for a few minutes.

5. Add the Blackberry Swirl

Once the blackberry sauce has cooled slightly, spoon the sauce onto the cheesecake filling in various spots across the surface. To create that iconic swirl effect:

• Use a toothpick or a knife to gently drag the blackberry sauce around in a swirling motion. This step adds a beautiful marbled look to the cheesecake bars.

6. Bake the Cheesecake Bars

Place the baking dish in the oven and bake for 40-50 minutes, or until the center of the cheesecake is mostly set but still a little jiggly when you give it a gentle shake.

7. Cool and Chill

Once baked, carefully remove the cheesecake bars from the oven. Let them cool at room temperature for about an hour. Afterward, transfer the dish to the refrigerator and allow the cheesecake to chill for at least 4 hours, though overnight chilling is even better for the best texture and flavor.