Rinse and drain the lenses. Peel and chop the onion. Clean or peel, wash and chop the soup vegetables and potatoes.
Heat the oil in a large, ovenproof pot. Sauté the onion until transparent. Add greens, potatoes and lentils and fry briefly. Sprinkle with curry and sauté. Season with salt, pepper and 1 pinch of sugar. Pour in about 1.5 l water, stir in broth. Cover and cook in a preheated oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer) for 1-1 1⁄4 hours.
Peel the pistachios for the topping. Wash the parsley and chop both roughly. Finely dice the apricots. Mix everything.
Season soup with salt, pepper and 1 pinch of sugar. Serve with pistachio topping.