Soak the lentils in 3/4 liter of cold water the day before. The following day, boil them in the soaking water, add a little salt and cook in a closed saucepan for about 20 minutes.
Cut the meat into finger-thick slices at the beginning, then into thumb-long strips. Cut the lemon into slices. Mix the meat, lemon, 3 tbsp. oil and coriander together and leave for a good 30 minutes.
In the meantime, remove the peel from the carrots and celery and cut into slices. Remove the peel from the onions and garlic. Cut onions into rings, chop garlic. 4.
Heat the remaining oil in a saucepan. Pour in the meat mixture and brown heartily. Then add the vegetables, onions and garlic and brown them at a high temperature as well.
Blanch (scald) the tomatoes, peel and quarter them. Cut the apricots in half. Add the lentils with the cooking water to the meat. Add tomatoes and apricots and heat. Season with salt, pepper, clear soup, curry and sugar.