Preheat oven to 350 degrees. Butter a 9x13 baking dish.
Heat oil in a large skillet. Add meat and brown very well, breaking meat up with a spoon or fork. Drain any accumulated fat. Spoon into prepared baking dish.
Layer zucchini over the meat. Sprinkle cheeses over the zucchini. Pour sauce over all.
Bake for 20-30 minutes. Let cool for 15 minutes. Cut and serve. Makes 6-8 servings. Enjoy!