Fill a small baking dish with 1/2 to 3/4 of an inch of water.
Cut the spaghetti squash in half and place flat side down in the water. Cover with foil and bake for 40 minutes.
In a small bowl, combine ricotta, Parmesan, parsley, Italian seasoning and salt and pepper. Use a garlic press to crush the garlic clove and add it to the mixture.
When the squash is finished cooking, allow it to cool long enough to be handled. Use a fork or spoon to scrape the flesh of the cooked squash. Use long strokes lengthwise and the squash will come out looking much like spaghetti.
Empty the water out of the baking dish and spray it with fat free cooking spray. Return the squash flesh to the baking dish.
Combine the ricotta mixture with the squash and spread evenly in the baking dish.
Spread the spaghetti sauce over the squash and ricotta mixture and spread the mozzarella cheese evenly over the top. Sprinkle more parsley flakes over the top to add color.
Bake uncovered in the 350 oven for 30 minutes or until the mozzarella begins to bubble and turn brown.
Allow the dish to cool for 5-10 minutes before eating.