Slice eggplants crosswise and soak in salted water for an hour. Drain and squeeze the aubergines. Heat plenty of sunflower oil in a pan and fry the aubergines until golden brown. Drain on kitchen paper and set aside. Chop the onions and garlic and sauté in the butter or olive oil until translucent.
Add the minced lamb and fry for 3-4 minutes. Add the ketchup, cinnamon and basil / oregano and cook for 4-5 minutes until the liquid has evaporated. Season the mixture with salt and pepper. Layer the eggplant and minced meat in an ovenproof dish, with the top and bottom layers made of eggplant.
Melt the butter in a saucepan for the sauce. Remove from the fire and stir in enough flour for a thick burn. Now pour in the milk and stir over medium heat until a thick, smooth sauce is formed. (For a richer sauce you can add 1-2 egg yolks in the stage - first whisk the egg yolks with a little hot sauce, then add to the saucepan and beat vigorously.) Season with salt and nutmeg. Then use a spoon to spread the sauce evenly over the top layer of eggplant. Bake for 25-30 minutes, until the surface turns brown. Serve immediately.