Cube tofu and put in a small plastic food bag. Add soy sauce. Seal bag and marinate tofu in soy sauce while you prepare the rest of the dish. Turn the bag over from time to time to marinate the tofu well. Wash millet in a bowl and then drain. Saute millet in sesame oil until it gets toasted and smells nutty. Add the water and simmer 20 minutes. Preheat oven to 180 degrees C. Add tofu, onion, mushrooms, celery, parsley, and sage to millet. Cook 10 more minutes. Add tahini and stir gently to blend. Put mixture in casserole dish, adding soy cheese. Bake 10 minutes at 180 degrees C.