In the skillet over medium heat, drizzle olive oil in the bottom of the pan; Add the chopped onion and minced garlic. Immediately add the rest of the ingredients, in order, except the cheese. Cover and simmer over low heat until onions, peppers, and squash are cooked as desired, approximately 20 minutes, stirring occasionally. Turn heat off. Sprinkle cheese on top, cover again until cheese is melted. Serve with grilled chicken or fish.

HINTS: I sliced all the veggies julienne style (in strips) to allow the them to cook more evenly. I used Rotel tomatoes since I could not find the fresh salsa in my local supermarket. I drained the juice from the tomatoes because the veggies will produce plenty of liquid while cooking. I preferred to drain most of the juice from the cooked mixture before adding about 1 cup of the shredded cheese to make it a little thicker.