Heat oven to 375 to 400 degrees, Cut squash in half and remove seeds. Rub cut flesh with salt and place flesh side down in baking dish. Bake for about 35 minutes. Meanwhile saute onion in marg until clear. Add Broccoli, mushrooms and celery. Saute about 4 minutes.
Stir in walnuts and basil. Then sprinkle with brown sugar and soy sauce. Toss to mix well. Check squash with fork to see if it goes through flesh. Stuff with veggie mixture. Top with 1 slice of munster chesse & return to oven for about 5 minutes.