It most certainly is not, Marie Callendar to the contrary. Around here, we make that plenty, but it is called "meat pie", since there is nothing to do with a pot.
Real, Pennsylvania Dutch-style pot pie, or "bot boi" in the dialect, more resembles brothy soup with noodles. I usually make it with wild game, as that is primarily how we feed our family, but you could certainly substitute a whole, cut-up chicken (or chicken legs) for the squirrels that I'm using here. Or even just vegetables- but you will need to use eggs and dairy in the noodes, so I don't think you could do a vegan pot pie. (Yes, I said squirrels- next time you see them hanging around your bird feeder, you can use this to threaten them!)
Whatever meat you decide to use, make sure that you trim off any fat or skin, because you do not need that greasy-ness in a dish like this. (Obviously, we take the skin off the squirrels, but there is virtually no fat to trim. Wild game is not bred to be fatty, like conventional meat.)
In a large stock pot or dutch oven, cover the meat with water, add some salt and pepper and two peeled and sliced garlic cloves. Let that simmer for an hour or two, then add a chopped onions, carrots and celery. (Note gratutious shot of my aqua Club cast aluminum dutch oven! ;)
Simmer the meat and vegetables for another hour or two until tender. Remove the meat to a separate bowl to cool and bring the broth & veggies to a boil while you make the noodles.
Sift together 2 cups of flour and a pinch of salt. Add 3/4 cup sour cream and one lightly beaten egg. The sour cream gives the noodles a nice bite and also some elasticity that you would not get with butter.
Cut the dough into 2" squares with a sharp knife- this is the classic "pot pie" noodle shape, but if you wanted to make them skinnier, no one would care!
Add the noodles to the boiling broth.
Let them cook for about a half-hour, while you prepare the meat.
Separate the (by now, cooled-off) meat from the bones. With squirrels, this is very labor-intensive, but with chicken it should go pretty fast. Discard the bones.
Add the meat back to the pot and about a tbsp of fresh chopped parsley.
Heat it through and enjoy real PA Dutch "pot pie"!