Combine cornstarch and water in a small bowl, stirring until dissolved; set aside.

In a heavy-bottomed pan, combine blueberries, granulated sugar, water, and lemon juice; simmer over medium-high heat for about 5 minutes.

Stir constantly until blueberries begin to break down.

Stir in the cornstarch mixture and bring to a low boil; cook for another 2-3 minutes until thickened.

Transfer sauce to a heat-proof bowl; cool for about 30 minutes, then chill in the fridge for 1-2 hours.

Line the bottom and sides of a 9-inch springform pan with parchment paper.

In a bowl, combine graham cracker crumbs, sugar, and melted butter until evenly moist.

Press the mixture firmly into the bottom and halfway up the sides of the prepared pan; place in the freezer.

In a large bowl, whip heavy cream and sugar on medium-high speed until stiff peaks form, about 2-3 minutes.

In another bowl, mix cream cheese, sugar, and vanilla extract until creamy and lump-free, about 2 minutes.

Fold cooled blueberry sauce into the cream cheese mixture until well combined.

Gently fold in whipped cream in parts to maintain volume; transfer filling to crust, spreading evenly.

Chill assembled cheesecake in the fridge overnight.