1. Saute the onion, garlic, and celery in oil until the onion is soft and clear. Add the potatoes and carrots, and cook for about 5 minutes, until thoroughly coated and the carrots start to soften.
2. Stir in the stewed tomatoes and then the textured soy protein. You might have to add a bit of water if the textured soy protein really soaks up everything. There should be some liquid to help it cook, but it shouldn't be soup.
3. Cover the pan and let the mixture cook for a bit while the oven preheats to 375 degrees F. I usually let it cook on the stove for 10-15 minutes. Season, to taste. When the oven's hot and the potatoes are starting to soften, fill the crusts and put them in the oven for 30 minutes.
4. After 30 minutes, check the potatoes. If they are pretty much done, put the cheese on top and bake for another 7-10 minutes. If they aren't, let the pies cook for awhile longer.
This freezes great and reheats great. Trust me, though, its extremely filling!