My potato soup began many years ago as a way to use up leftovers from Thanksgiving dinner. Basically, here's what I do:
Cook up some bacon till crisp and set aside for now
in the same frying pan saute onion and celery till soft with parsley, salt and pepper. (if you have leftover stuffing use that instead)
Either make fresh mashed potatoes or use leftover and put in a nice big pot. Add more milk and double strong chicken stock (add some extra bouillon) till the mashed potatoes are as thin or thick as you desire. If you have leftover gravy throw that in too. It's excellent with the gravy added.
Add your veggies and let it simmer for a bit to meld the flavors.
(sorry there are no specific measurements but that all depends on how much mashed potatoes you have)
Put into bowls and top with some cheddar cheese and the bacon crumbles.
Enjoy!!