Boil the eggplants in boiling water for 6-7 minutes and drain. Fry the chopped onion in oil. Add tomato paste to the roasted onions. Add the aubergines, washed rice, bulgur, black pepper and salt and stir them after frying for a few more minutes. Cook for 25 minutes on low heat. After resting for 10 minutes, serve with strained yogurt if you wish.