5 large eggs, room temperature * 2 tablespoons cornstarch
2 cups (one pint) sour cream, room temperature * 1 1/2 cups sugar
4 8-ounce packages cream cheese, room temperature
8 tablespoons (one stick) unsalted butter, room temperature
1 1/2 teaspoons vanilla extract * 1 teaspoon fresh lemon juice
1 teaspoon grated lemon zest
Generously butter the inside of a 10-inch spring form pan. Wrap a double layer of heavy-duty aluminum foil tightly around the outside of the bottom and sides, crimping and pleating the foil to make it conform to the pan. This will help to prevent water from seeping into the pan while it bakes. Position the baking rack in the center of the oven; preheat to 300* Fahrenheit.
In a large mixing bowl, use an electric mixer to blend the eggs into the sour cream. In a medium-sized bowl, blend the cream cheese into the butter until smooth and creamy. Add this to the egg-sour cream mixture and mix until smooth. Add the sugar, cornstarch, vanilla, lemon juice and lemon zest and beat thoroughly for 2 minutes. Pour into the prepared spring-form pan and place it in a roasting pan (or other pan) large enough to prevent the sides from touching. Place in the oven and carefully pour in enough very hot tap water to reach halfway up the sides of the spring-form pan.
Bake for 2 hours, 15 minutes, or until the cake is very lightly colored and a knife inserted in the center emerges clean. Remove from the water bath and carefully peel the aluminum foil from around the pan. Let stand at room temperature until completely cool, about 4 hours. Refrigerate, covered, until well chilled. For best flavor and texture, this cheesecake is best chilled overnight.