In a large skillet, saute the onion and garlic in the olive oil over medium high heat. Saute about 5 minutes or until the onions are soft, and then add in the zucchini. Cook, stirring occasionally, for another 5 minutes. Add the can of tomatoes, stirring to combine. Cover the pan, reduce the heat to medium low, and then let the mixture simmer while the gnocchi cooks according to it’s package directions.
Drain the gnocchi when it’s done cooking.
Add salt and pepper, to taste, to the zucchini mixture and stir. Gently stir the gnocchi into the zucchini mixture and let everything simmer together for about a minute. Remove the skillet from the heat.
Spoon half of the gnocchi mixture into a 8 or 9 inch square baking dish that has been sprayed with cooking spray. Take half of the mozzarella cheese and sprinkle it on top of the gnocchi mixture. Layer the remaining gnocchi on top of the cheese and then arrange the remaining cheese over that layer of gnocchi.
Bake, uncovered, at 350 degrees for 25 minutes. Turn the broiler of your oven on and broil, watching carefully, for 2-3 minutes until the top begins to brown.
Serve & enjoy!