Spaghetti squash and zucchini casserole

1 spaghetti squash (I used 1/2 of a 3.3 lb. squash
                              = 1.5 kg Courge Spaghetti
 1 medium zucchini (Italian squash) grated
 1 cup tomato sauce (or 1 6 oz. can tomato paste + 2 oz water)
 1 tsp dried or finely cut fresh basil
 1 tsp dried crushed oregano
 1 tsp garlic powder (or two cloves finely chopped fresh)
 1/4 tsp fresh ground black pepper
 1/4 tsp salt (optional)
 serrano chili sauce (or any other hot sauce) to taste (optional)
 
 (This dish requires 20 minutes of baking, but the first part of
 the preparation of the spaghetti squash can be done stovetop
 or microwave.
      
 Cut spaghetti squash in half length-wise. Carefuly scrape out
 seeds, but do not cut into the body of the squash. While the 
 squash is cooking you can prepare the other ingredients.
      
 Stovetop: place half squash cut side down in a pot with 2" (5 cm)
 water, cover and boil for 20 minutes.
 Microwave: place half squash in a dish with 1/4 cup water, cover
 with plastic wrap and cook at high (>600 watts) for 7 minutes.
      
 Squash is half cooked. With fork, scrape out squash to produce
 spaghetti-like strands. A thin, hard shell will be left.
      
 In a large bowl, add spaghetti squash, tomato sauce, grated 
 zucchini and spices. Mix well and spoon into squash shell (or 
 casserole dish), top with nutritional yeast, a little more 
 garlic powder (and, if desired, non-fat grated parmesan cheese).
      
 Bake at 350 degrees F. (175 C.) for 20 minutes or until done.
 
 Nutritional Analysis:
 Each 8 oz (.25 l.) serving has 66 calories, less than 0.25 g fat.
 
 Notes:
 
 I served it with brown rice and fresh non-fat French Bread.
 It would be an ideal filling for a pita pocket or tortilla.
       
 What to do with the other half of the squash?  Stick it in the 
 refrigerator for a few days, then prepare it as shown above, 
 except microwave for 10 minutes or boil for 30, and then scrape
 it out and serve topped with your favorite spaghetti sauce. 
 
 Time:     
 This took about 8 minutes of working time, 7 minutes of
 microwaving while getting the rest ready, and then waiting
 20 minutes while it baked. Smell and taste was delicious.
 Source:a sticker attached to a spaghetti squash by Linden Associated Growers,
Linden, CA.
 Makes: 6 servings.