NEW YORK — Menus across the country are introducing classic sandwiches with gourmet twists. Take the Meatball Sandwich at The Salty Pig in Boston, for example, which serves the sub-shop staple with pork and beef meatballs made with bone marrow, garlic and parsley, plus ricotta and Parmesan on ciabatta bread.

The item made Zagat’s recent list of the 14 hottest new sandwiches in U.S. restaurants. Featuring house-made condiments, charcuterie-style meat and artisanal bread, these bold favorites add serious sophistication to a lunchtime standby. Several of the concepts include bread from local bakeries, and Lucky’s Puccias in Austin serves sandwiches on bread baked in a wood-fired oven, resulting in a crusty exterior with a soft, pillowy center.

Click for a slideshow of Zagat’s top picks.