1 tbsp. olive or canola oil
2 yellow squash, sliced
2 zucchini squash, sliced
1 medium onion, sliced and separated
1 (8 oz.) jar taco sauce
1 large tomato, cut into wedges
1/2 tsp. oregano
1/4 tsp. salt
1/2 tsp. pepper
1 (8 oz.) pkg. shredded Mexican cheese

Heat oil in nonstick skillet or Dutch oven over medium heat until hot. Add squash and onion. Cook and stir 5 minutes or until vegetables are crisp-tender. Add tomato slices and oregano. Cook and stir for 1 minute. Sprinkle with salt and pepper. Add taco sauce and cook and stir for 30 seconds. Reduce heat to low. Sprinkle with cheese; cover and cook for 2 minutes or until cheese has melted.