Preheat the oven to 375°F. Wrap a 9-inch springform pan with heavy-duty aluminum foil to cover the bottom and sides, and lightly spray the interior with nonstick cooking spray.

In a medium bowl, mix the graham cracker crumbs, melted butter, granulated sugar, and salt until well combined. Press the mixture evenly into the bottom of the prepared pan and a little bit up the sides.

Bake the crust for 10 minutes until set, then remove the pan from the oven and set aside.

Lower the oven temperature to 325°F. In a large mixing bowl, beat the cream cheese, sugar, and flour until smooth. Then add the vanilla extract, lemon zest, lemon juice, and salt. Mix in the eggs one at a time until just combined, and finally stir in the sour cream. Avoid over-mixing to keep the batter smooth.

Pour the batter over the pre-baked crust. Place the filled pan in a larger roasting pan and pour boiling water into the roasting pan until it comes up about 1 inch along the side of the cheesecake pan. Bake for 1.5 hours or until the edges set and the center has a slight jiggle. If the cheesecake begins to brown too soon, cover it with foil until it is fully baked.

Turn off the oven and let the cheesecake cool in the water bath for about 45 minutes, then remove the pan from the bath. Cover the cheesecake and refrigerate for at least 8 hours or overnight before serving.

Serve with whipped cream and fresh fruit if desired.