For the bean salad with tuna, soak the beans overnight.
Cook the soaked beans with the quartered onion, sage leaves, peppercorns and soup seasoning until soft.
Wash the young onion, cut the green part diagonally into pieces, dice the white part.
Scald tomatoes, skin, halve, remove seeds and cut into pieces. Drain and chop the tuna.
Mix a marinade of vinegar, oil, salt and pepper.
Mix beans, green onion, tomatoes and tuna, mix with the marinade, season again and let the bean salad with tuna stand for a while.