Wash the meat, dab dry and cut into cubes. Clean the leek, wash carefully and cut into pieces. Heat oil in a pan. Brown the chicken cubes all around. Add the leek and fry for 2 minutes.
Season with salt and curry paste. Add lentils, deglaze with broth and simmer for about 10 minutes. Stir yoghurt and starch until smooth and thicken the stock with it. Bring to the boil briefly, season to taste again and serve.