Clean, wash and halve the aubergines and cut them lengthwise. Place on an oiled baking tray with the cut surface facing down. Pre-bake in a hot oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for 25-30 minutes
Soak the buns. Peel and chop the onions. Fry half of them in 3 tablespoons of hot oil. Stir in tomato paste and sauté briefly. Deglaze with 150 ml water and tomatoes with their juice, bring to the boil. Stir in stock. Crush tomatoes a little bit. Season with salt and pepper. Simmer for about 5 minutes.
Wash the oregano and, except for one thing, chop it. Squeeze the buns well. Knead with minced meat, egg, rest of onions, oregano and spices
Place the aubergines in an oiled casserole dish with the cut surface facing upwards. Press the flesh aside. Season with salt and pepper. Put the minced dough in the middle
Add the tomato sauce. Sprinkle everything with parmesan. Bake in a hot oven at the same temperature for about 45 minutes. Garnish with the remaining oregano. Serve with rice