Slice the eggplants either peeled or with skin on, into rounds, ½ inch thick. Season generously with salt and layer in a colander placed in the sink. Let this sit for 20-30 minutes. The bitter liquid will be released. Gently squeeze and pat dry with a paper towel .
Place some flour in a shallow pan for dredging. Place the beaten eggs in another shallow bowl. Heat a large frying pan on medium -high heat with about 1 inch of vegetable oil.
Dip the slices of eggplant in the flour and coat evenly. Next , dip the eggplant slices in the beaten egg and allow the excess to drip off. Fry in the hot oil until golden brown on both sides. Drain on a paper towel lined tray.
Puree the tomato sauce with a blender or immersion blender when cooled and then add the oregano. Add ½ cup of water to thin down the sauce. Add ample sauce on the bottom of a baking dish, I prefer stone or earthenware. Layer the eggplant , overlapping slightly. Spoon more sauce on top to cover the eggplant. Sprinkle both cheeses on top.
Cover tightly with aluminum foil and bake in a preheated 400 degree /180 degree oven for approximately 20 minutes , or until the sauce is bubbling and cheese is melted. Remove the foil for the last few minutes of baking and allow the cheese to cook to a golden colour.