Heat the oven to 325°F (165°C). Line a standard 12-cup muffin pan with paper liners. This temperature is gentle enough to bake the cheesecake centers without excessive browning.

In a bowl, stir together the graham cracker crumbs, sugar, melted butter, and salt until evenly moistened. The mixture should resemble damp sand and hold together when pressed.

Divide the crumb mixture evenly among the 12 liners, using about 1 1/2 tablespoons per cup. Press firmly into an even layer. Bake for 5 minutes, then remove from the oven and let cool for a few minutes while preparing the filling.

Beat the softened cream cheese and sugar on medium-low speed until smooth, about 1–2 minutes. Add the flour, lemon zest, lemon juice, and vanilla and mix just until combined. Scrape down the bowl as needed.

Add the eggs one at a time, mixing on low speed just until each egg disappears into the batter. Avoid whipping excessive air into the filling. The finished batter should be smooth, thick, and pourable.

Divide the cheesecake batter evenly among the cooled crusts, filling each liner about 3/4 full. Gently tap the pan once or twice on the counter to release large air bubbles.

Bake at 325°F (165°C) for 18–22 minutes. The edges should look set while the centers still have a small, controlled jiggle when the pan is gently moved. Do not wait for the centers to become completely firm.

Place the muffin pan on a wire rack and let the cheesecakes cool at room temperature for about 30 minutes. Once they are no longer warm, refrigerate for at least 2 hours, preferably 3 hours, before adding the blueberry topping.

Reserve 1/2 cup (75 g) of the blueberries for finishing. Add the remaining 1 cup (150 g) blueberries, sugar, and lemon juice to a small saucepan. Cook over medium heat for 3–4 minutes, stirring occasionally, until several berries burst and release their juices.

Stir together the cornstarch and water in a small bowl until smooth. Add the slurry to the simmering blueberries and cook for 1–2 minutes, stirring constantly, until the mixture thickens enough to coat a spoon. Remove from the heat and cool completely.

Spoon the cooled blueberry topping over the chilled cheesecakes. Finish each with a few of the reserved fresh blueberries. For clean presentation, remove the paper liners just before serving. Keep the cheesecakes refrigerated until ready to eat.