Prepare the Crust:
Preheat oven to 325°F (163°C).
Mix graham cracker crumbs, sugar, and melted butter until combined.
Press firmly into a 9-inch springform pan and bake for 8 minutes. Let cool.
Make the Cheesecake Filling:
In a large bowl, beat cream cheese and sugar until smooth.
Add eggs one at a time, mixing after each.
Mix in sour cream, lemon zest, lemon juice, and vanilla until creamy.
Pour over cooled crust and smooth the top.
Bake the Cheesecake:
Wrap the bottom of the springform pan with foil and place it in a water bath.
Bake for 50-60 minutes, until the edges are set and the center is slightly wobbly.
Turn off the oven, crack the door, and let it cool inside for 1 hour.
Prepare the Blueberry Topping:
In a saucepan, combine blueberries, sugar, and lemon juice over medium heat.
Stir in cornstarch mixture and cook until thickened (about 5 minutes). Let cool.
Chill And Serve:
Once the cheesecake reaches room temperature, refrigerate for at least 4 hours (overnight is best).
Top with blueberry sauce before serving.