Using a hand mixer or a stand mixer fitted with a whisk attachment, whip the cold heavy cream into stiff peaks on medium-high speed, about 4-5 minutes. Set aside.
Using a hand mixer or a stand mixer fitted with a whisk or paddle attachment, beat the cream cheese and granulated sugar together on medium speed until perfectly smooth and creamy. Scrape down the sides and up the bottom of the bowl with a rubber spatula as needed. Add the confectioners’ sugar, sour cream, lemon juice, and vanilla extract.
Beat for 2-3 minutes on medium-high speed until smooth and combined. Make sure there are no large lumps of cream cheese. If there are lumps, keep beating until smooth.
Using your mixer on low speed or a rubber spatula, fold the whipped cream into the cheesecake filling until combined. This takes several turns of your rubber spatula. Combine slowly as you don’t want to deflate all the air in the whipped cream.
Remove crust from the freezer and spread filling into crust. Use and spatula to smooth down the top.
Cover tightly with plastic wrap or aluminum foil and refrigerate for at least 6-8 hours and up to 2 days. For best results, 12 hours is best. I chill mine overnight. The longer refrigerated, the nicer the no-bake cheesecake will set up.
Use a knife to loosen the chilled cheesecake from the rim of the springform pan, then remove the rim. Using a clean sharp knife, cut into slices for serving. For neat slices, wipe the knife clean between each slice.