Whisk together pumpkin, eggs, brown sugar, cream, vanilla, and liqueur (if using) in a bowl until combined. (You can also mix in a Vitamix.)
Stir together granulated sugar, cornstarch, cinnamon, nutmeg, ginger, and salt in a large bowl.
Add cream cheese and beat with an electric mixer at high speed until creamy and smooth, about 3 minutes. Reduce speed to medium, then add pumpkin mixture and beat until smooth.
Pour filling into crust, smoothing top, then put springform pan in a shallow baking pan (in case springform leaks).
Bake until center is just set, 50 to 60 minutes. Transfer to rack and cool 5 minutes. (Leave oven on.)