Bombacigno's. Pop's. Johnnie's. In Chicagoland, legendary Italian beef sandwich joints dot the junk food landscape. Here in the bay area? Not so much. Rosamunde used to serve a stellar version that lost its menu spot due to lack of interest. Both street cart Da Beef and SOMA neighbor The Grill do respectable renditions using the tried and true Vienna brand but neither are exactly destination worthy. So leave it to Tony Gemignani, who pulls off serving 13 styles of pizza between his two sit-down eateries, to take on an authentic Italian beef sandwich ($11) at the Chicago themed Capo's.Gemignani starts with Snake River Farms Kobe Bottom Round (OK, we can attest to the fact that there's no name-checking of meat in Skokie) that he braises then slow roasts to rare in the brick oven. After being sliced thin, the beef cooks in hot au jus and then a roughly half-pound fistful is plucked and dropped onto a crusty roll from nearby Italian French Bakery. Sticklers might opine that the roll is too sturdy but we appreciated that it sopped up the sea of aus jus without disintegrating. In Chicago, locals pay as much credence to a restaurant's giardiniera (an Italian-American vinegar relish) as they do to the beef itself and Capo's interpretation, featuring Serrano peppers, celery, spices, olive oil, bell peppers and green olives, veers toward the traditional. The combination of the beef and the giardiniera results in a wallop of brawny flavor with a slight after burn from the peppers. Mozzarella cheese is added mainly for texture though purists might ask for their sandwich without it. Throw in a pile of near-perfect waffle fries, rendered a little fiery by a dusting of Calabrese powder, and a house pickle spear and you've got yourself quite a lunch. One caveat though. It's only available during lunch, which is only served Friday through Sunday. Get your calendar out. It's worth it. Capo's, 641 Vallejo St., 986-8998. sfcapos.com.