Prepare the Crust:

1. Preheat your oven to 325°F (160°C) and grease a 9-inch springform pan.
2. In a medium bowl, combine graham cracker crumbs, sugar, and melted vegan butter. Stir until the mixture resembles wet sand.
3. Press the mixture firmly into the bottom of the prepared pan to form an even layer.
4. Bake for 8-10 minutes, then set aside to cool.

2. Make the Raspberry Swirl:

1. In a small saucepan, combine raspberries, sugar, lemon juice, and cornstarch.
2. Cook over medium heat, stirring frequently, until the raspberries break down and the mixture thickens (about 5-7 minutes).
3. Allow the mixture to cool slightly before using.

3. Prepare the Cheesecake Filling:

1. In a large mixing bowl, beat vegan cream cheese and granulated sugar together until smooth and creamy.
2. Add vegan sour cream, vanilla extract, and optional lemon juice. Mix until well combined.
3. Gradually add aquafaba (or egg replacer) one tablespoon at a time, mixing on low speed to avoid overmixing.

4. Assemble the Cheesecake:

1. Pour the cheesecake filling over the cooled crust, spreading it evenly with a spatula.
2. Drop spoonfuls of the raspberry mixture onto the surface of the cheesecake. Use a toothpick or knife to swirl the raspberry sauce into the filling, creating a marbled effect.

5. Bake and Cool:

1. Place the cheesecake in the oven and bake for 50-60 minutes, or until the edges are set but the center jiggles slightly.
2. Turn off the oven, crack the door open, and let the cheesecake cool inside the oven for 1 hour.
3. Transfer the cheesecake to the refrigerator and chill for at least 4 hours or overnight for the best results.

6. Add the Finishing Touches:

1. Top the chilled cheesecake with vegan whipped cream and garnish with lemon slices for a fresh and elegant presentation.
2. Slice and serve cold.