Preheat the oven to 350°F.
In a stand mixer, mix cream cheese, cornstarch, and sugar until smooth.
Add lemon zest, lemon juice, vanilla, and sour cream, mix for 1 minute.
Add eggs and yolks one at a time, mixing until combined.
Pour the batter into the prepared pan.
Place the pan in a roasting pan, pour boiling water into the roasting pan.
Bake for 1 hour, then let it cool in the oven with the door cracked for 1 more hour.
Chill the cheesecake in the fridge for at least 8 hours.