Sausage-Stuffed Squash

2 medium acorn squash
1 tablespoons butter
8 ounces mild bulk pork sausage
1/2 cup celery, chopped
2 tablespoons onion, diced
1 medium apple, peeled, cored, diced
1 teaspoon white flour
1 large egg
1/4 cup sour cream
1/8 teaspoon salt
1/3 cup Velveeta cheese, diced

Cut squash in half, scooping out seeds.  Place face down in baking dish and bake in 350 degree oven until tender (about 1 hour).  Meanwhile make the filling.  In a large frying pan, melt butter and fry the sausage, celery and onion until meat is no longer pink.  Stir in apple and fry for a couple of minutes.  In a small bowl, combine the flour, egg, sour cream, and salt until smooth.  Combine with sausage.  Fill squash with sausage mixture.  Bake, until heated through, about 15 minutes.  Serves 4.