Take your double cream and put it into a mixer with a whip attachment. Whip into stiff peeks and set aside.
In a clean bowl, add in your cream cheese and powdered sugar. Whip until combined.
Add in sour cream and vanilla, whip to combine.
Add back in your stiff peeked double cream, and either hand fold or mix in using your mixer.
You can now taste the filling to see if it is as sweet as you'd like. If you want, you can add more vanilla, powdered sugar, or even some lemon for some tartness.
Scoup the filling into a graham cracker pie shell and let sit in the fridge for at least an hour to set up.
When serving, spoon over Opies Black Cherries in Kirsch and some of the syrup, to have the best experience.