Crust
1 Cup flour
1/4 Cup Sugar
1 tsp. lemon zest
1/8 tsp salt
1 Stick unsalted butter (chilled and cut into pieces)
Filling
1 Tbs. plus 2 tsp. cornstarch
1/2 Cup cold water
2 egg whites
3/4 C sugar
1/4 C fresh lemon juice
Cheesecake
1 1/4 lb cream cheese softened
2 Tbs flour
3 large eggs at room temperature
1/4 C sour cream (room temp)
1 tsp vanilla
1. Make the crust
Preheat oven to 325 with rack in center position. Butter 9 inch springform pan. In a food processor pulse flour with sugar, lemon zest and salt. Add butter and pulse till crumbly dough forms. Press into bottom of spring form pan and bake for 20 min.
2. Make the filling. Dissolve corn starch in water. In a medium saucepan whisk the egg whites with the sugar and lemon juice. Whisk in cornstarch mixture and cook over moderate heat stirring until sugar is dissolved and mixture hot, about 4 min. Boil over moderately high heat for 1 min. whisking constantly until mixture is thick and glossy. Transfer to heat proof bowl, add lemon zest and cool.
3. In a large bowl using an electric mixer beat the cream cheese with 1 cup sugar until smooth. Mix in flour till blended. Add the eggs one at a time, add sour cream and vanilla and mix until smooth. Pour batter over crust and smooth. Lollop lemon mixture onto the cheesecake batter and swirl with a knife.
4. Bake cheesecake at 320 for 50 min. Leave it oven for one hour before removing to prevent cracks. Can also bake with pan of water below to help with even baking.
