Italians ask for and eat only what's in season, and they eat a lot of it. Locals shop outdoor markets daily for the freshest produce or grow their own. Restaurants supplement entrées with plate after plate of contorno, or peak-season vegetable sides, depending on the time of year. But it's simple additions that really characterize this outstanding cuisine—what are very commonplace ingredients come together for extraordinary results. Learn which details lie at the heart of Italian cooking.