Cut squash length wise and remove seeds. Wash thoroughly in cold water and pat dry. Season olive oil with garlic powder and onion powder.
(Note: Oil can be seasoned with other herbs or spices as desired, such as rosemary, oregano, sweet marjoram, fresh basil, red pepper flakes, salt and pepper, or parsley.)
Pre-heat grill to 400°F. Brush squash on one side with seasoned olive oil and place face down on grill. Cover for 6 to 10 minutes then brush top of squash with olive oil, turn over and cover again. Repeat this process until squash is golden brown on both sides. Serve hot with bowl side upwards. Sprinkle with cheese of choice.