Meanwhile, cut squash lengthwise in half. Use spoon to scoop out seeds and membranes; discard. Place squash, cut sides down, in microwaveable baking dish. Add enough water to dish to fill to 1-inch depth. Microwave on HIGH 12 min. or until squash can easily be pierced with fork. Cool slightly. Use fork to scrape squash into spaghetti-like strands.