If using fresh beans: Shell them, put them in a pot with enough cold, unsalted water to cover by about 2 inches, bring the water to a gentle simmer, cover the pot, and cook at a slow, steady pace until tender, about 45 minutes to 1 hour. Time their preparation so they will still be warm when assembling the salad.
If using dried beans: Time their cooking so that they are still warm when you put together the salad.
If using radicchio: Detach the leaves from the head, discarding any blemished ones, shred them into narrow strips about ¼ inch wide, soak in cold water for a few minutes, drain, and either spin-dry or shake dry in a towel.
If using endive: Discard any blemished leaves, take a thin slice off the root end, then cut it across into strips ¼ inch wide, washing it and drying it as described above.
Drain the beans and put them, while they are still warm, into a serving bowl with the radicchio or endive. Add salt, toss once, pour in enough oil to coat well, add a dash of vinegar, liberal grindings of black pepper, toss thoroughly, and serve at once.
