Preheat the oven to 325°F (160°C). Grease the springform pan and line the bottom with parchment paper.

In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter. Mix until well combined. Press the mixture evenly into the bottom of the prepared springform pan to form the crust. Bake for 10 minutes, then remove from the oven and allow to cool.

In a large mixing bowl, beat the softened cream cheese and sugar using an electric mixer until smooth and creamy.

Add the eggs one at a time, mixing well after each addition. Then, stir in the vanilla extract, lemon zest, lemon juice, and sour cream. Mix until all ingredients are well incorporated and smooth.

Pour the cheesecake filling over the cooled crust, spreading it evenly.

Bake for 50-60 minutes, or until the center is set but still slightly jiggly. Turn off the oven and leave the cheesecake inside for an additional hour to cool gradually.

Once cooled, remove the cheesecake from the oven, let it cool to room temperature, and then refrigerate for at least 4 hours or overnight.

For the blueberry topping, combine the blueberries, sugar, lemon juice, cornstarch, and water in a small saucepan over medium heat. Stir gently until the mixture thickens and starts to bubble, about 5-7 minutes. Remove from heat and let it cool.

Once the cheesecake is set and chilled, top it with the blueberry mixture before serving.

Serve the cheesecake chilled for the best texture and flavor.