This is an essential summer supper in my house, the kind of basic-with-a-twist recipe that I love. It's a riff on classic salade Nicoise, with most of the ingredients you find in that salad tossed instead with pasta, and it works spectacularly. It's light and fresh but completely satisfying, great hot or at room temperature, and manages to seem sort of special and elegant even though it's made with canned tuna. Not all canned tuna is created equal, however, and it's worth seeking out an Italian brand of olive-oil-packed tuna, which is superior in both flavor and texture to your typical store-bought tin of fish. It's more expensive, but still less expensive than making the same dish with fresh fish; sort of a happy compromise, I think.