Conventional wisdom has long held that the "softness" of New York's water—meaning it has comparatively low concentrations of calcium and magnesium—is why the city can claim it has the world's best bagels. While there is some logic to this (harder water toughens the gluten in dough), the real reason that the bagels are better here has more to do with technique than anything else.

When we talked to Baz Bagel & Restaurant at this year's Choice Eats, they confirmed the soft water theory is mostly myth, explaining that great bagels are a mix of ingredients and know-how. This week, Reactions' YouTube channel went even more in depth with a little help from chef Richard Coppedge of the Culinary Institute of America and Murray's Bagels.

There are two key steps that distinguish true New York City bagels. Chilling the dough rings for a few days—a process called proofing—allows for a longer, slower fermentation that releases unique flavor compounds. After they're chilled, New York bagels are boiled in a vat of water and malt barley for anywhere from 30 seconds to 3 minutes to pregelatinize the starch, giving them that chewy texture.

Chef Coppedge explained to NPR's The Salt that while this used to be the standard way to make bagels, many modern bakeries favor an automated, streamlined process that steams the bagels as they bake. 

"This steam will gelatinize the surface only, and encourage more color and shine, but not promote the unique chewiness, because the steam won't get to the starchy interior," Coppedge says. And as any New Yorker will tell you, you can really taste the difference.