The bialy is not a sub-type of bagel, it’s a thing all to itself. Round with a depressed middle filled with cooked onions and sometimes poppy seeds, it is simply baked (bagels are boiled then baked). Purists prefer them straight up, preferably no more than five hours after being pulled from the oven. Extinction.Like the Lowland gorilla, the cassette tape and Madagascar forest coconuts, the bialy is rapidly becoming extinct. Sure, if you live in New York (where the Jewish tenements on the Lower East Side once overflowed with Eastern European foodstuffs that are now hard to locate), you have a few decent options.he bialy is not a sub-type of bagel, it’s a thing all to itself. Round with a depressed middle filled with cooked onions and sometimes poppy seeds, it is simply baked (bagels are boiled then baked). Purists prefer them straight up, preferably no more than five hours after being pulled from the oven. Extinction.