Peel and chop the onion and garlic. Peel, wash and chop the carrot. Heat butter and oil in a large pot. Sauté onion, garlic and carrot for about 3 minutes at medium heat.
Add the lentils and chilli to the vegetables and steam for about 2 minutes. Add tomatoes together with juice and 400 ml water. Chop the tomatoes slightly. Bring everything to the boil and simmer for about 10 minutes.
Quarter the apricots, stir into the soup and continue cooking for about 10 minutes. Season lentil soup with salt, pepper and 1 pinch of sugar.