Beat cream cheese and sugars until fluffy. Add vanilla and cornstarch, beat until just combined.
Add eggs one at a time, then fold in sour cream.
Pour the mixture into the cooled crust, tap the pan to release air bubbles.
Place the pan in a water bath, bake at 350ºF for 20 minutes, then reduce to 300ºF for 35 minutes. Turn off the oven and let it sit for 1 hour.
Cool at room temperature for an hour, then refrigerate for 6-8 hours or overnight.