Add the cream cheese to a stand mixer fitted with a paddle attachment and cream at medium speed until smooth. Scrape down the sides of the bowl.
24 ounces cream cheese
Add the powdered sugar, sour cream, lemon juice, and vanilla extract and mix at low speed until the sugar is incorporated then increase the speed to high and whip for 1 minute. Scraping down the sides as needed so everything is evenly combined and there are no lumps.
1 cup powdered sugar, ¼ cup sour cream, 1 tablespoon lemon juice, 2 teaspoons vanilla extract
Fold in the cool whip with a rubber spatula until evenly incorporated. The mixture will be thick and stiff.
16 ounces Extra Creamy Cool-Whip
Spread the filling mixture out in the prepared crust, the filling may come above the crust in the pan, but that's okay. Make sure to really press the filling in since it's a bit aerated and you don't want large bubbles. Just be careful around the edges so you don't pull the crust back into the filling. Smooth out the top and cover with aluminum foil.
Chill in the refrigerator for 8 hours. When ready to slice, run a chef's knife under hot water to heat the blade, then slice. Clean and heat the blade after each slice for clean and even cuts.