DirectionsPreheat oven 350F Butter and flour 9 inch springform pan.
Wrap the bottom in two layers of aluminum foil.
Place a deep pan, large enough to fit the springform pan into, in the oven as it preheats and fill it with about 1 inch water.
In bowl of a food process or mixer, combine ricotta and cream cheese and combine until smooth.
Add in sugar, mix until sugar dissolves in the cheeses, then add cornstarch.
Add in the eggs one at a time, waiting until each is fully incorporated before adding the next one.
Add lemon zest and vanilla and mix until well blended.
Pour mixture into prepared pan.
Place pan into waterbath that has been heating in theoven.
Bake for 65-75 minutes, until the top is lightly browned, but the center should still jiggle slightly when the pan is GENTLY shaken.
TURN OFF THE OVEN.
DO NOT REMOVE CHEESECAKE LEAVE IN OVEN WITH DOOR CLOSED UNTIL COOLED.
THIS KEEPS IT FROM CRACKING.
Remove and chill overnight in fridge before serving.