To a large mixing bowl, add cream cheese and sugar. Using a hand mixer, beat until smooth, scraping down the sides of the bowl as needed.
Add the peanut butter, sour cream, and vanilla extract. Blend until smooth and creamy, scraping down the sides of the bowl as needed.
To a separate large mixing bowl, add heavy cream.
Start mixing at the lowest speed, gradually increasing the speed to medium until the cream starts to thicken.
When the cream begins to thicken, reduce speed to low.
Slowly add confectioners' sugar. Then, increase to medium speed and eventually to high speed until stiff peaks form. (Stiff peaks refer to the whipped cream peaks that stand straight up and hold their shape firmly.) Be cautious to avoid splattering.
Gently fold the whipped cream into the cream cheese mixture until completely combined.
Divide the filling evenly between the cooled peanut butter crusts.