The restaurant named for a highway that cuts through Campagna just keeps rolling, leading diners on a tour of a southern Italian region blessed with sharp and simple (but serious) cuisine. As has long been his habit, chef Nate Appleman takes interesting side trips: He picks hard-to-come-by Friarelli peppers and roasts them sweet and whole with anchovies, lemon, breadcrumbs, and chilies. He makes earthy squid-ink gramigna (a kind of curly bucatini), and delivers it al dente with tender octopus and borlotti beans. Appleman finds beauty in the basics, quick-firing blistered marinara pizza and drizzling clouds of burrata with salt and olive oil. But this remains a restaurant with a fresh perspective, its energy unsapped by expansion. An unusual wine list, drawn largely from small Italian producers, and tail-to-snout charcuterie underscore A16’s emphasis on the authentic. (J.S.)