Street food is trendy, and Rome’s Trapizzino is one of its trendiest ambassadors. Invented in 2008 in the Testaccio neighborhood of the Italian capital, the half-sandwich, half-pizza treat has been so successful that, in just a few years, it has expanded not only beyond its birth neighborhood, and national borders, it has even opened in New York and Japan – and it plans for more openings. So what is trapizzino and why is it so successful?

Trapizzino is a play on words that comes from the union of the words tramezzino (the classic Italian triangular sandwich found in many bars) and pizza; trapizzino is half sandwich, half pizza. The dough is that of pizza, shaped in the form of a triangle, made with lievito madre (starter), soft inside, crunchy outside. Then, rather than tomato and mozzarella, it is filled with classic Roman dishes, which take hours, if not days, to make. So Trapizzino has been able to combine tradition and quality with quick delivery and convenient prices, which is probably the secret of its success.