1. Preheat the oven to 325°F and line a 12-cup muffin pan with paper liners.

2. In a bowl, mix the graham cracker crumbs, 3 tablespoons sugar, and melted butter until the texture looks like wet sand.

3. Divide the crust mixture evenly among the liners and press it firmly into the bottom of each cup.

4. Bake the crusts for 5 minutes, then set aside to cool slightly.

5. In a large bowl, beat the cream cheese until smooth.

6. Add 1/2 cup sugar and mix until creamy.

7. Blend in the sour cream, vanilla extract, lemon juice, and lemon zest.

8. Add the eggs one at a time, mixing on low speed just until combined.

9. Divide the cheesecake filling evenly over the crusts.

10. Bake for 16 to 18 minutes, until the centers are just set with a slight jiggle.

11. Let the cheesecakes cool in the pan for 30 minutes, then transfer them to the refrigerator and chill for at least 3 hours.

12. In a small saucepan, combine the blueberries, 3 tablespoons sugar, cornstarch, water, and 1 teaspoon lemon juice.

13. Cook over medium heat for 4 to 6 minutes, stirring gently, until the blueberries soften and the sauce thickens.

14. Let the topping cool completely.

15. Spoon the blueberry topping over the chilled mini cheesecakes before serving.