In a saucepan over medium heat, combine fresh blueberries, sugar, and lemon juice. Cook for 5-7 minutes until berries begin to soften, then mix cornstarch with water and add to thicken, about 2-3 minutes. Set aside to cool.

Preheat your oven to 325°F (160°C) to ensure your cheesecakes bake evenly.

Line two muffin pans with 14 cupcake liners evenly.

In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter until resembling wet sand. Press into each liner and bake the crusts for 5 minutes, then set aside.

In a large bowl, beat cream cheese and sugar until smooth. Gradually add lemon juice, zest, and vanilla, then add eggs one at a time, mixing on low speed until just combined.

Fill each muffin liner with cheesecake batter, then spoon blueberry topping onto each and swirl with a toothpick.

Bake for 17-20 minutes until tops are slightly set with a jiggle in the center.

Turn off the oven and let cheesecake sit for 1 hour with the door ajar, then chill in the fridge for at least 3-4 hours.