Mix meat, onions, bread crumbs, egg and 2 Tbsp. dressing just until blended. Divide into 12 portions. Press 1 cheese cube into center of each meat portion, then roll into ball.
Heat remaining dressing in large skillet on medium-high heat. Add meatballs; cook 8 to 10 min. or until lightly browned, turning frequently. Stir in tomatoes; simmer 10 min. or until meatballs are done (160ºF), stirring occasionally.
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.
Serve squash topped with meatballs.
The spaghetti squash can be cooked ahead of time. Microwave squash and pull into strands as directed; place in large microwaveable bowl. Cool, then refrigerate up to 2 days. Discard both squash shells. When ready to serve, microwave squash on HIGH 3 to 5 min. or until heated through. Add remaining ingredients; mix lightly with fork. Microwave 2 min. or until heated through.
Sprinkle with 1/4 cup KRAFT Grated Parmesan Cheese before serving.
Calories From Fat
% Daily Value*
Total Fat 16g
Saturated Fat 7g
Trans Fat 0g
Total Carbohydrates 29g
Dietary Fibers 5g
* Percent Daily Values are based on a 2,000 calorie diet.
* Nutrition information is estimated based on the ingredients and cooking instructions as described in each recipe and is intended to be used for informational purposes only. Please note that nutrition details may vary based on methods of preparation, origin and freshness of ingredients used.