Make the crust: In a bowl, mix graham crumbs, melted butter, sugar, and salt until the crumbs are evenly moistened and sandy.
Portion the crust: Spoon 2–3 tablespoons into each cup. Press down firmly with the back of a spoon to create an even base.
Chill while you make the filling.
Whip the cream: In a cold bowl, whip the heavy cream to medium-stiff peaks. Set aside.
Beat the cream cheese: In another bowl, beat cream cheese until smooth. Add powdered sugar, vanilla, lemon juice, zest, and a pinch of salt.
Beat until fluffy and no lumps remain.
Fold together: Gently fold the whipped cream into the cream cheese mixture in two additions. Stop as soon as it’s smooth and airy.
Fill the cups: Spoon or pipe the cheesecake filling over the crusts, leaving space on top for blueberries. Smooth the surface.
Chill at least 2 hours to set.
Make the blueberry topping: In a small saucepan, add blueberries, sugar, and lemon juice. Cook over medium heat for 3–5 minutes, stirring, until the berries release juices. For a thicker sauce, stir in the cornstarch slurry and simmer 30–60 seconds until glossy.
Cool completely: Let the blueberry mixture cool to room temperature.
It will thicken slightly as it cools.
Assemble: Spoon cooled blueberry topping over the chilled cheesecake cups. Garnish with fresh blueberries if you like.
Chill and serve: Chill another 30 minutes for cleaner layers, or serve right away if you’re eager.