Clean and wash the aubergines and cut them in half lengthwise. Remove 2/3 of the flesh and chop finely. Peel and finely chop the onion and garlic. Wash, clean and dice the tomatoes.
Knead the minced meat, onion, garlic and chopped aubergines. Season with salt and pepper. Wash oregano and dab dry. Put something aside for garnishing. Pluck off the remaining leaves. Chop 2/3 of the leaves and mix with two tablespoons of tomato cubes.
Season the aubergine halves with salt and spread the minced meat on top. Put the rest of the tomatoes and broth in a casserole dish. Put aubergine halves into it. Bake in the preheated oven (electric: 200 °C/ gas: level 3) for 45 minutes.
Sprinkle cheese on the minced meat five minutes before the end of the cooking time. Sprinkle aubergines with remaining oregano leaves and serve garnished with a bouquet of herbs.