Just two weeks after Burger King announced it was partnering with Impossible Foods to offer a new meatless burger, Del Taco has announced it’s partnering with Beyond Meat to offer new meatless tacos.

For the uninitiated, Del Taco is a restaurant chain that sells Mexican food in 580 locations across the US. Now it’s also the first Mexican fast-food concept to sell tacos with Beyond Meat. Starting April 25, the new “Beyond Tacos” will be available in all 580 stores. There’ll be vegetarian (with cheese) and vegan versions. Both sell for $2.49 (the standard taco is $1.49).

The partnership is further evidence that plant-based meat is going mainstream, and fast. Startups like Beyond Meat and Impossible Foods are racing to team up with traditionally meat-focused restaurant chains that can introduce plant-based meat to a wide consumer base.

“Definitely there’s a sense that there’s a movement going on that’s much bigger than any one company,” Ethan Brown, the founder and CEO of Beyond Meat, told me. “I think competition is good — it helps to grow awareness of the sector.”

For their part, the chains are eager to partner with the startups because customers are increasingly seeking out meat alternatives, including for health reasons. Chains know there’s profit to be made here.

This is a hugely encouraging shift for those who want to see meat alternatives replace actual meat because of concerns over animal cruelty or climate change. If plant-based meat scales up, it could help save hundreds of thousands of animals from suffering on factory farms, and it could fight global warming by reducing the number of methane-producing cattle. It could also combat other problems like antibiotic resistance.

Beyond Meat’s culinary team worked with Del Taco to create new recipes with the chain’s signature seasoning. If you’re a vegetarian, you can get a taco that includes Beyond Meat plant-based crumbles, grated cheddar cheese, lettuce, and diced tomatoes. If you’re a vegan, you can get a taco with avocado instead of cheese. And if you’re just not in a taco mood, you can order something else off the Del Taco menu — say, burritos or nachos — and get them to swap out the protein for Beyond Meat.

The flexibility differentiates Del Taco’s approach from Burger King’s. Although the latter is offering an “Impossible Whopper” that contains zero beef, it’s not a vegan meal: It comes doused in the same mayo the chain uses on all its regular Whoppers.

Brown, the Beyond Meat founder, became a vegan after questioning why we extend moral concern to some types of animals but not others. Yet he told me he recognizes the importance of giving people lots of options. “I have a strong commitment to meeting people where they are,” he said.

He told me 93 percent of consumers putting Beyond Meat in their basket at the store are also putting in some type of meat product. That’s not a problem to him — on the contrary, he’s proud of that statistic. It shows that plant-based meat doesn’t only appeal to vegans like him. “I’m so sensitive to not being seen as extreme,” he said. “We’re all about mainstream.”

His startup has already had some mainstream success. In January, Carl’s Jr. restaurants started offering a veggie burger made by Beyond Meat. And when A&W began offering a “Beyond Burger” in Canada last year, it was a hit. Quesada recently became Canada’s first Mexican chain to offer the “Beyond Meat Burrito.”

So what’s the next frontier for expansion? A Change.org petition asking McDonald’s to add a meatless option has garnered more than 160,000 signatures and an endorsement from Ellen DeGeneres. McDonald’s has toyed with the idea before, releasing the McVegan in Finland in 2017, but so far hasn’t taken the plunge in the US.

“As the battle for the best meatless burger ramps up, McDonald’s is being left behind by its biggest rival,” petition starter Kathy Freston wrote in an emailed statement after Burger King announced its partnership with Impossible Foods.

When I asked Brown if Beyond Meat is in talks with McDonald’s, he told me he can’t say anything specific about that right now. But, he said, “We are talking to everybody.”

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