New York Cheesecake

Ingredients:
7 ounces graham crackers, crushed
1/4 cup/ 1/2 stick unsalted butter, melted
4 x 8-ounce packages cream cheese
Pinch of salt
1 1/2 cups superfine sugar
1 cup sour cream
2 teaspoons vanilla extract
1 tablespoon finely grated lemon zest
1 tablespoon lemon juice
4 eggs, beaten
2 egg yolks

Directions:
1. Preheat the oven to 300 Fahrenheit degree. Grease a 9-inch springform pan fitted with a flat base.
2. In a bowl, mix together the graham cracker crumbs and melted butter, then press this mixture evenly into the base of the prepared pan. Bake in the oven for 10 minutes, or until lightly browned, then remove from the oven and set aside to cool.
3. In a separate bowl, beat the cream cheese until soft and smooth. Add the salt and sugar and beat for 1 minute. Add the sour cream, vanilla extract, lemon zest and lemon juice and beat for a further 1 minute. Add the eggs and egg yolks and beat until well combined. Pour the mixture evenly over the graham cracker crust in the pan.
4. Bake in the oven for 45-50 minutes, or until the edges ar set but the center is still lightly soft. Turn off the oven, leave the cheesecake inside and leave the door ajar. Leave to cool in the oven for 45 minutes.
5. Remove the cheesecake from the oven and cool to room temprature. Remove from the pan, place on a serving plate, cover with foil, and refrigerate for at least 4 hours or preferably overnight, before serving.