Vegan Italian Meringue Buttercream. (Scott Suchman/For The Washington Post)

Imagine being a vegan in France and craving île flottante, or floating island, a dessert of fluffy puffs of meringue nestled in a sea of crème anglaise. Joël Roessel, a 34-year-old opera tenor, was riding on a bus near Paris and wondering how he could replace the main ingredient, so he asked himself, “What would disgust me as much as a raw egg white?”

His answer: bean liquid. When he got home, Roessel found a can of red beans in the cupboard, drained out the liquid and whipped it. The result was nothing short of astonishing: a mound of fluffy, pure white — but completely eggless — meringue.

This minor French revolution hit the world when Roessel published it on his blog, Révolution Végétale, in December 2014, and the concept quickly began to catch on with others, including Goose Wohlt. The American software engineer is credited with coining the word “aquafaba” — “aqua” for water and “faba” for beans — to describe the ingredient that most people simply pour down the sink. Wohlt posted his vegan baked meringue recipe — made from the liquid from a can of chickpeas, plus sugar — to a popular Facebook group called “What Fat Vegans Eat” in March. The post received nearly 500 comments in a matter of hours, quickly spawning a whole new Facebook group: “Vegan Meringue — Hits and Misses!”

Rebecca August, an animal-care provider in Michigan, is the original force behind the new group, serving as its head administrator since creating it just over six months ago, after she saw Wohlt’s original recipe. “I ran to my kitchen to whip up a batch of cannellini bean fluff, the closest thing to chickpeas I had on hand,” she recalls. “When I saw the amazing response to this discovery, I messaged Goose and told him that Vegan Meringue deserved its own Facebook page, and the phenomenon began.”

Vegan Butter. (Scott Suchman/For The Washington Post)

At more than 27,000 members worldwide and growing daily, the page is indeed a phenomenon, and aquafaba continues to garner attention, even making an appearance on the spring menu of chef Dan Barber’s food-waste-focused pop-up restaurant in Manhattan, WastED. The Facebook group experiments are wide and varied, from macarons and dacquoise to butter and mozzarella, with enthusiastic forays into challah, nougat and Yorkshire pudding. The cooks are just as varied and include vegans, omnivores, those with egg or gluten allergies and some who are simply “epicurious.”

“Goose conceived of the group as an open-source development group,” says August, “a sharing community where everyone benefits from and builds on the genius of others, and, I have to say, our group is just the best in that regard.”

The development concept is clearly embraced by the community, as members are not shy about sharing their aquafaba misses as eagerly as they do their hits, seeking to learn why a batch of aquafaba banana pancakes turned out mushy or how to rescue a drippy lemon meringue pie. As the experiments continue, novices are advised to use three tablespoons of aquafaba to equal one egg. The bean juice seems to work equally well whether it comes from a can or from a fresh batch of homemade cooked beans, and it can be frozen for later use. Although most any beans will do, including black, kidney and soy, chickpeas (a.k.a. garbanzo beans) tend to be the preferred variety for their milder, less “beany” flavor. Besides, you can whip up a batch of hummus to go with that aquafaba chocolate mousse at the same time.

But why does it work? Harold McGee, the food scientist who wrote the best-selling kitchen reference book “On Food and Cooking,” is guessing it has something to do with the combination of proteins, carbohydrates and saponins. “Saponins are soaplike materials that can collect in bubble walls at the interface between liquid and air and stabilize the bubbles,” McGee says in an e-mail. “Some proteins can do the same, and both proteins and carbohydrates help thicken the liquid, which makes it slower to drain out of the foam structure.”

August notes that aquafaba appears to embody many qualities found in eggs and even other dairy products. That has encouraged increasing innovation among those who have become inspired by the movement, and they have whipped aquafaba into Italian meringue buttercream, used it as a binder in baked goods and even blended it with oil to become a butter substitute.

Meanwhile, just outside Paris, Roussel continues to experiment with aquafaba, even using them (along with some added starch and guar gum) to make those elusive floating islands that started his quest in the first place. “What was really important to me,” he says, “before sharing my discovery, was to understand as far as I could how to help people in successfully replacing the foam.” Now he’s an active member of the Facebook vegan meringue community himself, benefiting as much as anyone else: “I’ve continued to experiment, and the misses of others gave me a progressive knowledge of what to do and not to do. Nothing’s impossible!”

Hartke is a food writer and editor in Washington.