Prepare the basic meatballs and set aside.
Melt the margarine in a large skillet.
Add the garlic, thyme leaves, mushrooms, and zucchini; cook over medium-high heat for about 5 minutes, stirring occasionally.
Add the cooked meatballs; cover and simmer, stirring occasionally, until the vegetables are tender, about 10 minutes.
Sprinkle with the salt and cheese.
Add the tomato wedges, cover and heat for 2 to 3 minutes.