At the rental-car return in Milan’s Malpensa airport, I take a last pensive sniff of our Fiat Panda. Someone should bottle the scent and call it Aroma Artigianale. The top notes are of roasted hazelnuts—the vaunted Piedmontese nocciole delle Langhe in the crumbly cookies eaten just an hour ago. The base notes: Amalfi lemons we’d picked off trees in Campania. In between is a faded porcine bouquet, mingling the expensive muskiness of three-year-old culatello ham from Emilia-Romagna with