Wash the potatoes and boil in water for about 20 minutes. Then quench, peel and let cool off
Rinse lenses cold. Simmer covered in a good 1/2 l boiling broth for 25-30 minutes
Peel and finely chop the onion. Bring to the boil with 1/8 l stock, add vinegar. Cut the potatoes into thick slices and let them stand for a while
If necessary, drain the lenses and let them cool down a little. Crumble the cheese. Add both with oil to the potatoes, season to taste
Clean, wash and shake dry the lettuce leaves. Line a plate with it and arrange the lukewarm potato and lentil salad on top. Garnish with marjoram if desired.