Arrange thinly sliced eggplant, tomato and zucchini in a deep casserole dish in alternating layers. Add crushed garlic cloves between occasional layers; sprinkle with olive oil and season with salt and pepper. Ratatouille is a traditional peasant dish...which would typically be all vegetarian. Or...you can slip in a layer of salami somewhere in the middle. SLOW cook at a LOW temp (250°) for 2 to 2 1/2 hours. Grate parmesan cheese over the top for the last 15 minutes.