When tiny Delfina expanded into the comparatively massive storefront next door, the restaurant became much more comfortable, more chic, and (if it was possible) even more popular. Happily, the exciting rustic Italian cooking stayed the same. Whether it's a deceptively simple pasta (spaghetti with plum tomatoes, garlic, olive oil, and hot chiles) or a more demanding risotto (perhaps made with butternut squash, fonduta, and truffle oil), everything is devised with care and prepared with a rigorous intensity that translates into compulsively edible food. (Unlike at many other Italian restaurants, the secondi are as good as the antipasti and the pastas.) A recent meal featured mint ravioli stuffed with lamb in a tasty lamb jus studded with fresh peas, an extraordinarily flavorful minestrone called an "aquacotta" (cooked water) floating a gently poached egg perched on a garlic crostino, grilled chicken liver spiedini with pancetta, and juicy quail with crumbled wild fennel sausage, followed by a clever assortment of Italian cheeses. Nobody in Italy -- or San Francisco -- was eating any better that night.