Preheat oven to broil. Place the zucchini and eggplant slices on a parchment covered baking sheet, toss with oil if you wish. Broil, flipping half way through, until slightly tender. This will depend on how thin you slice your vegetables, so turn when they're just starting to get golden brown.
Meanwhile, heat a large skillet over medium-high heat. When hot add the meat, Mesa de Vida healthy cooking sauce, crushed tomatoes and salt to taste. Cook, stirring often to break up the meat, until the meat is fully cooked and the sauce is slightly thickened. This should take about 10 minutes, which is just about when you're vegetables should be perfectly roasted. Turn the heat on the oven down to 350 degrees.
In a large casserole or baking dish layer the softened zucchini and eggplant with the meat sauce and cheese. Finish with a layer of the meat sauce, then a final topping of the parmesan (or cotija) cheese.
Bake for 25-30 minutes until golden brown and bubbly throughout. Rest for 10 minutes before cutting into slices.