New York (CNN Business) Burger King's Impossible Whopper is arriving at over 100 locations in the San Francisco Bay Area.

The San Francisco rollout marks a significant increase. Until Monday, about 200 locations in those four markets served the product.

Interest in plant-based protein has been heating up as consumers look for ways to reduce their environmental impacts and eat healthier., which also makes plant-based alternatives to meat, last week reported first quarter sales of $40.2 million — up 215% from the same period a year before.

Impossible is also seeing a spike. Since it launched a new version of its plant-based protein in January , sales have jumped 50%, the company said.

The Impossible Whopper has arrived in California.

"Sales in pretty much all our restaurants have been really surging," Impossible CEO Pat Brown told CNN Business. The company's product is available in over 9,000 restaurants.

It's been hard for Impossible to cope with the rapid acceleration in demand, and has experienced shortages

In an effort to keep up, Impossible's Oakland manufacturing facility now operates all day, every day, with employees working 12-hour shifts. The company is adding a production line and has nearly doubled its staff at the plant, from about 70 to roughly 130 over the course of about a month. Plus, its tapped experts from the tech industry to bulk up its leadership team.

"We are absolutely doing everything we possibly can" to make sure that "we're going to be able to deliver product" for future rollouts of the Impossible Whopper, Brown said. Burger King has about 7,000 restaurants nationwide.