Osso buco, a braised section of veal shank or shin with a bone filled with rich marrow, is a traditional Northern Italian specialty, though it does show up in other regions of the country.
It also makes appearances on menus across America. Recently American chefs have been experimenting more with osso buco, making it with lamb—which is occasionally done in Italy—and also with pork and even fish.
Lamb is the most popular variation. Marco Canora has made lamb osso buco at Hearth  in New York’s East Village . Goblin Market , another New York operation, serves braised baby lamb osso buco with creamy polenta, grilled fennel and red onion in a red wine sauce.
At Fireside in the Omni Berkshire Hotel in New York, Sam DeMarco has been serving a barbecued pork osso buco with creamy cheese grits.
“I always like to do a twist on traditional dishes,” DeMarco says. “People know osso buco, they understand it with the bone up the middle and all that, so this is fun.”
DeMarco turns the osso buco into a taste of the American South and makes his barbecue sauce with a popular soda.
But he recently took the pork off the menu and replaced it with a lamb osso buco seasoned with Indian spices, including cumin and ginger. He serves it with a yogurt-raita sauce and roasted cauliflower with curry and raisins.
Fish osso buco is another variation and is usually made with monk-fish. There is rarely any marrow in the bone, but using monkfish, which can be slowly braised like a piece of veal, is an effective way to update and lighten the traditional dish. It also transforms the dish from a cold weather stewlike preparation into a dish more suited to spring and summer.
There is a monkfish osso buco on the menu at the Metropolitan Club  restaurant in Chestnut Hills, Mass. Plaza Café  in Southampton, N.Y., is another spot for monkfish osso buco. It also has been served at Abboccato in New York.
The classic osso buco usually is served with gremolata, a mixture of minced garlic, lemon peel and parsley. New-style gremolatas are out there now, too, and they’re not just being served with osso buco.
For example, the short ribs at Twisted Restaurant in Phoenix come with a kumquat gremolata.
At Jer-Ne  in Marina del Rey, Calif., pan-seared foie gras is garnished with pistachio gremolata, and Ca del Sole in North Hollywood serves lemon-flavored gremolata to enliven schiacciata di pollo, boneless chicken.