Cut squash in half lengthwise; remove seeds. Place squash halves, cut side down, in a shallow baking dish and bake 40-45 minutes or until almost tender.
Meanwhile, dice cooking apples (to yield about 1 1/2 cups) and celery (1/4 c). Stir apples and celery together with walnuts, sugar and cinnamon.
Turn squash halves cut side up. Sprinkle lightly with salt.
Spoon apple mixture into squash halves and return to oven and bake, covered, about 25 minutes more or till apple is tender.
Slice in 1/4 inch pieces and cook in a skillet on the stove or in the oven until no longer pink in the middle. Season with salt and pepper. You could also throw the pork in a slow cooker for a few hours, and it will be perfectly shreddable! Serve about 3 ounces of meat with half an acorn squash and a wheat roll.