Prepare the Crust:
Preheat your oven to 325°F (163°C). Line a muffin tin with cupcake liners.
In a bowl, mix the graham cracker crumbs, sugar, and melted butter until combined.
Spoon about 1 tablespoon of the mixture into each liner and press down firmly with the back of a spoon. Bake for 5 minutes, then let cool.
Make the Cheesecake Filling:
In a large bowl, beat the cream cheese and sugar until smooth.
Add the eggs one at a time, mixing well after each addition.
Mix in the vanilla, flour, and sour cream until fully combined.
Divide the cheesecake batter evenly over the cooled crusts, filling each liner almost to the top.
Bake the Cupcakes:
Bake for 18-20 minutes, or until the centers are slightly jiggly but set.
Remove from the oven and let cool completely in the tin before transferring to the refrigerator to chill for at least 2 hours.
Prepare the Blueberry Topping:
In a saucepan over medium heat, combine blueberries, sugar, and lemon juice.
Cook until the blueberries release their juices, stirring occasionally.
Stir in the cornstarch mixture and cook until the sauce thickens, about 2 minutes. Let cool.
Assemble the Cupcakes:
Spoon the blueberry topping onto the chilled cheesecake cupcakes.
Serve immediately or refrigerate until ready to enjoy.