Step 1

Preheat oven to 300°F.

Step 2

Crush graham crackers in food processor or place in plastic bag and crush with a mallet or rolling pin.

Step 3

Stir together melted butter, graham cracker crumbs, and salt. Press mixture firmly into bottom and 3 inches up sides of 9" springform pan. Refrigerate 15 minutes.

Step 4

Meanwhile, place the cream cheese, ricotta, eggs, sugar, lemon juice, lemon zest, and vanilla in a food processor and process until smooth.

Step 5

Place the cornstarch and water in small bowl and mix until smooth. Add the cornstarch mixture to cheese mixture and mix to combine.

Step 6

Pour cheese mixture over the crust and bake for 1 hour and 10 minutes or until just set (cheesecake will jiggle slightly and firm up upon chilling).

Step 7

Turn the oven off and allow cake to cool in the oven with the door closed for 20 minutes or so. Remove from oven and place on rack to finish cooling.

Step 8

Refrigerate for at least four hours or (preferably) overnight. Top with whipped cream, if desired.