It is a safe guess that the Eastern European Jews who brought the bialy from Bialystok to New York City, piecing back together the recipe for this plain but beguiling dimpled roll in their new world after fleeing their old one, did not do it so that one day it could be sliced open and stuffed with a New Jersey pork sausage that comes in a cloth sack.

To be fair, this was not the original plan at Shelsky’s Brooklyn Bagels, either. The idea was to serve pork roll, egg and cheese sandwiches on a kaiser roll or one of the bakery’s palm-size, hand-rolled bagels. Peter Shelsky, the bakery’s owner, grew up in Manhattan, but he knew that some good things come from New Jersey, particularly pork roll, which he wanted to sell in the mornings.

Also known as Taylor ham, pork roll is a cured, smoked and cooked meat product that has the tightly pebbled appearance of engineered stone, like a Corian countertop made of flesh. Pressing sliced pork roll on a hot griddle intensifies its saltiness while giving it a hint of a crust that contrasts attractively with the slightly spongy interior. Griddled pork roll, combined with a cooked egg and a slice of American cheese, is eaten across New Jersey as a breakfast sandwich.

Usually it is found on a kaiser roll. Sometimes it is seen on a bagel. But some Shelsky’s customers requested it on a freshly baked bialy, and others followed, and now pork roll sandwiches made on bialys are nearly as popular as the ones made on rolls, with bagels a distant third.