Pour enough vegetable oil into a large frying pan to coat.
Fry eggplant gently until browned on both sides.
Add more oil as necessary.
Turn down heat, add vegetables, pour tomato sauce over all.
If tomato sauce does not contain herbs, add oregano and sweet basil to taste.
Add black pepper if needed.
Sprinkle cheeses on top.
Cover tightly and let simmer until eggplant is tender (30 minutes or less.)