5 large eggs, room temperature
2 cups (one pint) sour cream, room temperature
4 8-ounce packages cream cheese, room temperature
8 tablespoons (one stick) unsalted butter, room temperature
1 1/2 cups sugar
2 tablespoons cornstarch
1 1/2 teaspoons vanilla extract
1 teaspoon fresh lemon juice
1 teaspoon grated lemon zest
Generously butter the inside of a 10-inch springform pan. Wrap a double layer of heavy-duty aluminum foil tightly around the outside bottom and sides, crimping and pleating the foil to make it conform to the pan. This will help to prevent water seeping into the pan when you put it into the bain-marie. Position the baking rack in the center of the oven; preheat the oven to 300* Fahrenheit.
In a large mixing bowl, using an electric mixer, beat the eggs with the sour cream until well blended.
In a medium-sized bowl, beat the cream cheese with the butter until smooth and creamy. Add this to the egg-sour cream mixture and beat until smooth.
Add the sugar, cornstarch, vanilla, lemon juice and lemon zest and beat thoroughly, about 2 minutes.
Pour into the prepared springform pan and place 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 springform 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.
**My Notes: I can't stress enough how important it is to let those first 4 ingredients in this recipe come to room temperature. I've hurried the cream cheese and have had unsightly lumps of it in my batter.
**I've italicized the mixing instructions to emphasize blending the ingredients to achieve the desired texture.
** Have a platter or other large dish that will hold the hot and drippy springform pan after you remove it from the bain-marie. When you remove the bain-marie from the oven, the water is very hot, so please exercise extreme caution.
Before removing the roasting pan, have a plan on where you are going to set it so you are not holding the pan, desperately searching for a clear space to set it down. I find it impossible to remove the cheesecake from the bain-marie while it is in the oven, so I remove the entire set-up from the oven. I make every effort not to burn my wrists or the back of my hands while removing the springform pan; I haven't been burned yet, but I have soaked the edges of the potholders in the hot water, and it's amazing how fast that steaming water is wicked up to my tender fingers!
**When you first remove the cheesecake from the oven, it looks light and puffy, and there may be some hairline cracks in the top. Do not despair. As the cheesecake cools, it will gently deflate and the hairline cracks disappear.