Pierce squash several times with a fork, and place on paper towels in microwave oven. Microwave at HIGH 10 to 12 minutes or until tender, turning squash halfway through cooking time. Let stand 5 minutes. Cut squash in half lengthwise, and discard seeds. Remove spaghetti-like strands with a fork to yield 2 cups. Coat a nonstick skillet with cooking spray; place over medium heat until hot. Add squash; cook 8 minutes, stirring occasionally. Press squash evenly along bottom and sides of skillet, forming a crust. Combine egg whites and next 5 ingredients in a bowl; stir with a wire whisk. Pour into squash shell, and sprinkle with cheese. Cover and cook over medium-low heat 5 minutes or until set. Serve warm. Yield: 4 servings. Nutritional Value per serving: Calories 70 (24% from fat), protein 7g, fat 1.9g (sat 1g mono 0.5g, Poly 0.2g), Carb 6.1g, Fiber 1.1g, Chol 4mg, iron 0.7mg, Sodium 245mg, calcium 100mg veg 11