When the Impossible Burger made its 2017 debut at Toasted, Megan Yarmuth’s chain of sandwich and burger joints in central Florida, she committed to serving it as a classic burger: medium rare, with caramelized onions, lettuce, tomatoes and cheese.

Every day, Yarmuth and her team would take pounds of the custom reddish-looking faux-meat from the refrigerator, shape it into patties and put them on the grill. After three minutes, the burgers developed a crust like real ground beef.

The Impossible Burger is engineered to taste, cook, and smell just like meat. But it isn’t. It’s made from plant-based ingredients: wheat and potato protein, coconut oil, and soy and yeast extracts. At first, Yarmuth mainly served the burgers to curious foodies and vegans — some of whom had driven from other parts of the state to try a new product they’d heard about from friends elsewhere.

The plant-based Impossible Burger is engineered to taste, cook, and smell just like meat.

Now, it’s also popular with meat eaters who are watching their cholesterol and weight.

“They love this burger because they don’t feel like they are compromising,” Yarmuth said. “They don’t feel like they’re eating a black bean burger that has zero comparison to beef.”

The Impossible Burger is now available in 5,000 fast food outlets across the country, including Wahlburgers and White Castle. It’s a product of Impossible Foods, a company conceived in Silicon Valley and backed by numerous investors, including Microsoft co-founder Bill Gates. It’s vying for supremacy in the fake-beef market with the Beyond Burger from Beyond Meat, which is on the menu at Carl’s Jr, TGI Friday’s and available in the meat section at Whole Foods and more than 13,000 other grocery stores.

Both companies made their debut in 2016, marketing their products to entice meat eaters away from animal meat by replicating as closely as possible with plant-based ingredients. Impossible Foods launched at a restaurant with a meat-rich menu owned by celebrity chef David Chang. Meanwhile, Beyond Meat launched in Whole Foods, next to packages of ground beef.

Chuck Muth, chief growth officer at Beyond Meat, says vegans and vegetarians represent a small, niche market compared to meat eaters.

“It’s a much bigger target audience, so from an economic perspective, roughly over one-third of consumers today are meat reducers,” said Muth, referring to meat eaters who are consciously cutting down on meat consumption for health or environmental reasons.

The Impossible Burger is now available in 5,000 fast food outlets across the country, including Wahlburgers and White Castle

Trade group the Plant Based Foods Association projects U.S. sales of plant-based proteins like the burgers will reach $5 billion by next year — nine times more than in 2012. Health-conscious 20 and 30-somethings are driving the growth. Melanie Zanoza Bartelme, global food analyst at Mintel, said Impossible Burger and Beyond Meat are marketing their plant-based products as more than just food.

“Their environmental messaging and really talking about the amount of water and land and resources that their products are saving — that’s really just one of the key attributes that are making these products really attractive to consumers,” she said.

Both companies have been marketing the unfamiliar products by placing them in familiar settings — fast-food restaurants, neighborhood burger joints, and supermarkets.

“This is really making these brands, in particular, really approachable and really stand out for consumers,” Bartelme added.

Impossible Foods and Beyond Meat have been marketing plant-based burgers by placing them in familiar settings — fast-food restaurants, neighborhood burger joints, and supermarkets.

It’s okay to have a plant-based burger if you think it’s helping to save the world, says plant-based dietitian Julieanna Hever — just don’t expect it to keep you healthy. She said she sees more and more non-meat eaters who are starting to have the same health issues as meat eaters because they’re consuming plant-based products that are engineered to mimic meat.

“All of these different compounds that we’re trying to avoid by eating a plant-based diet, we’re eating by consuming this animal-free version of it,” said Hever.

It could take years of science to know for sure, according to Hever.

Meanwhile, Impossible Burger has just launched version 2.0 of its product. The company says it’ll be in grocery stores soon. Beyond Meat has also launched a plant-based sausage that the company says “look, sizzle, and satisfy like pork.”