Place the graham crackers in a food processor or put them in a plastic bag and crush them with a rolling pin until you have fine, sandy crumbs.
Pour the melted butter over the crumbs and stir or shake until evenly coated; the mixture should look like wet sand.
Press the crumb mixture firmly into the bottom of a 9-inch springform pan, using the back of a spoon or your fingers to create an even, compact crust. Chill in the refrigerator while preparing the filling.
In a large mixing bowl, beat the softened cream cheese and sugar together with a spatula or hand mixer until smooth, creamy, and free of lumps.
Stir in the fresh lemon juice and vanilla extract, mixing until fully incorporated and the filling is bright and slightly thickened.
In a separate bowl, whip the chilled heavy cream until soft peaks form, with a gentle, airy texture.
Carefully fold the whipped cream into the cream cheese mixture, using a spatula to combine gently until smooth and fluffy.
Pour the creamy filling over the chilled crust, spreading it evenly with a spatula to create a smooth, level top.
Place the cheesecake in the refrigerator and chill for at least 4 hours, or overnight, until set and firm.
Once chilled and set, remove the sides of the springform pan, slice, and serve chilled. Garnish with fresh fruit or a drizzle of lemon if desired.
