Peel the eggplants and dice or cut them into round slices, salt and leave them to sit for a bit to drain away the bitterness. Wash and dry them with a paper towel.
Fry them until semi-cooked in half the heated oil. In the remaining oil, braise the onions and flour, add the semi-fried eggplants, tomatoes and finely chopped parsley. Salt and season them with black pepper.
Finally, add the feta cheese/cheese and stir. Pour the mixture into a suitably sized oven dish, pour on the eggs beaten with the milk and bake in a moderate oven.