On Rye ordered custom cups to serve its egg creams. (Ilyse Fishman Lerner)

Surely I'm not the only person to have been traumatized by school cafeteria chocolate milk. You know, the kind in the little impossible-to-open cartons, where it seemed like half of what you tasted was paper.

Well, my friends, I eventually found the antidote for the sins of the past, and it is the egg cream.

The first thing you ought to know about the egg cream is printed in big white text on the custom-made cups at On Rye, a new sandwich shop in Chinatown inspired by Jewish delis: "No eggs or cream were harmed in the making of this drink." Instead, it's a fizzy mix of chocolate syrup (Fox's U-bet is the brand of tradition), milk and seltzer water. The origins of both the concept and the strange name are the subject of much debate.

I first tasted an egg cream last year at the boisterous subterranean dining room of New York landmark Famous Sammy's Roumanian Restaurant and fell in love. I've been thrilled to see it showing up on menus at new places opening around Washington, including Slim's Diner, the Bird and On Rye. Egg creams are also on the menu at Union Market staple Buffalo & Bergen, where there are three flavors: chocolate, vanilla and Nutella.

"They're delicious," said On Rye founder Ilyse Fishman Lerner. "They wash down the food really well."

Believe her. The carbonation is refreshing, and the seltzer and not overly sweet Fox's syrup mean the end result isn't cloying.

"People are very curious" about the drink, Lerner said. But there are also plenty of her customers who know exactly what they're ordering. "It's such a nostalgic drink for people," she said.

Perfecting the egg cream, which has to be made to order, for a busy setting took some research and development, particularly when it came to getting the bubbles just right and the ability to survive at least a little while in a to-go cup.

"For a fast-casual sandwich shop to carry this, it didn't make sense," Lerner said. "But it was something we really wanted to do."

$3 at On Rye, 740 Sixth St. NW.

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