I can never give quantities. The only stipulation is good tuna canned in good olive oil.
Blanched green beans are also a Niçoise staple, for me, and I love the floppy bowls of Boston lettuce leaves. Just-hard boiled eggs and chunks of boiled potato are good (to suck up the vinaigrette), and as part of that vinaigrette, I include about 1/3 cup very finely chopped red onion (leave it to macerate in the vinegar before adding salt, sugar, pepper, and extra virgin olive oil - in that order). Cherry tomatoes cut in half, oil-cured black olives are never a bad idea. Strips of raw red pepper, and coils of green garlic scapes, cooked till tender, would be nice.
Freshly toasted sourdough, rubbed with a clove of garlic, off to once, and you're set. Add icy white wine and the world is a good place for a while.
