Beverly Hills Cheesecake

2 (9 inch) prepared graham cracker crusts

2 (8 ounce) packages cream cheese

2 ½ teaspoons grated lemon zest

1 teaspoon vanilla extract

½ cup white sugar

3 eggs

2 cups sour cream

½ cup white sugar

1 teaspoon vanilla extract

Preheat oven to 350 degrees F (175 degrees C).

Mix together the cream cheese, lemon zest and vanilla until smooth. Stir in 1/2 cup sugar, then beat in the eggs, one at a time until blended.

Pour the cheesecake mixture into the prepared graham cracker crusts, being careful to distribute it evenly. Shake the pans gently to settle the batter, then bake in the preheated oven for 25 minutes. Remove the cheesecakes, but do not turn off the oven. Allow cheesecakes to cool 20 minutes before topping.

For the sour cream topping: Whisk together the sour cream, 1/2 cup sugar and vanilla until blended. Distribute the topping mixture over the two cooled cheesecakes. Bake cheesecakes in 350 degree F (175 degrees C) oven for an additional 10 minutes. Cool completely, then refrigerate until serving.