5 c. sliced potatoes
3 c. sliced zucchini
2 sm. or 1 med. onion
1 1/2 c. shredded cheddar cheese
1/3 c. grated Parmesan cheese
1 lb. Italian sausage (optional)
2 tbsp. oil
1 clove garlic, mashed
1/2 tsp. each thyme, basil and oregano
1/3 c. milk (preferably buttermilk)
Salt and pepper to taste