Preheat your oven to 375°F (190°C). This helps get it nice and hot for baking.
Take a cake pan and wrap it with heavy-duty aluminum foil. Make sure the foil covers the bottom and extends up the sides to keep the water out.
Now, spray the inside of the pan with non-stick cooking spray. This step is important to avoid any sticking later on.
In a large bowl, whisk together the eggs and sour cream until it’s smooth. An electric mixer makes this part easy!
In another bowl, mix the cream cheese and butter until they are nice and smooth. Then, combine it with the sour cream mixture and whisk until it’s all blended well.
Add the sugar, vanilla, lemon zest, lemon juice, and cornstarch. Mix everything on low speed until it’s well combined.
Pour the cheesecake mixture into the prepared cake pan. Place this inside a larger roasting pan. Carefully pour boiling water into the roasting pan, around the cheesecake pan, until the water reaches about an inch high.
Bake everything for about 1 hour 30 minutes to 1 hour 45 minutes. The cheesecake should be set but still slightly jiggly in the center when done.
Let the cheesecake cool in the water bath for about 45 minutes. Then, take it out and remove the foil and the sides of the pan.