Slice eggplant lengthwise into ¼ inch slices and arrange on a plate. Salt the eggplant (about 1 teaspoon) and let sit.
In a saute pan on medium, heat 2 Tablespoons oil. Cook the sliced onions in the oil stirring often for about 30 minutes until completely caramelized. Remove from pan. Preheat oven to 350 degrees F.
Pat the eggplant dry with a paper towel.
In a rectangular baking dish drizzle 1 teaspoon olive oil on the bottom. Add a small layer of chopped tomatoes.
Then layer eggplant, caramelized onions, more tomatoes, garlic, oregano, a sprinkle of salt and pepper, and a small drizzle of oil (around 1 teaspoon for each layer).
Continue layering until all ingredients are used up.
Bake at 350 covered for 1 hour and 15 minutes.
Serve as a side dish or an appetizer with bread to dip in the juices.
