My wife's grandmother had a 'Christmas Coffee Cake' recipe that we tried to make several times and it never came out right (or at least matching my wife's recollection of what it tasted and looked like.)
It called for 'sour cream', and I've always suspected that given the age of the recipe it was really using heavy cream that had gone sour rather than the cultured stuff you get at the grocery store these days.
I've wondered about using creme fraiche to make it, as I think it is a lot closer to traditional 'sour cream'. These days I tend to keep heavy cream on hand for keto cooking and baking, I could also try letting a cup of it sit on the counter to go sour.
I'll see if I can find the recipe (it's in the Nebraska Centennial Cookbook, which my wife's mother edited) and post it.