For the black salsify salad, place the brushed and peeled black salsify on the spot in a large enough bowl with water and the squeezed juice of a lemon to prevent them from turning brown.
Cut the roots into 4 cm long pieces and cook them in a little salted water for 10-15 minutes. Cook salsify while still hot with the hot marinade of vegetable soup, vinegar, salt and sugar. Add oil and marinate for a few hours. Pour the marinade over them frequently.
Arrange the lettuce on a large plate and surround it with a thick wreath of tomato slices or possibly grated radishes or possibly herbs or possibly lettuce leaves. It goes well with boiled ham.