The cult favorite Shake Shack burger chain is expanding in the South Bay with not one but two restaurants in the coming days.

The first, in Sunnyvale, will start grilling Wednesday, April 1, on Murphy Avenue at the Cityline retail and housing district. A ribbon-cutting at 9:30 a.m. will precede the 10 a.m. opening. On this first day of service, Shake Shack will donate $1 from every sandwich sold to Sunnyvale Community Services, a hunger and poverty nonprofit.

Next, Shake Shack will open a Mountain View location at The Village at San Antonio at 10 a.m. Thursday, April 9. One dollar from every sandwich sold that day will be donated to the nonprofit Mountain View Community Foundation.

Both days, Shake Shack will hand out free tote bags to “the first wave” of customers.

The openings coincide with the introduction of the restaurants’ newest seasonal specials: sandwiches topped with pimento cheese, the piquant Southern spread rarely seen in this part of the country. Shake Shack’s version is made with aged cheddar and peppers, and it will be available for a limited time.

The fast-casual restaurant was founded as a hot-dog cart in a New York City park but quickly became known for its all-natural Angus beef burgers. However, there’s still an all-natural Vienna beef “flat-top dog” on the menu — along with cage-free chicken sandwiches, crinkle-cut French fries and hand-spun milkshakes.

Counting these two restaurants, Shake Shack now operates at 17 locations in the Bay Area and 52 total in California.

Details: Operating hours for both locations will be 10 a.m. to 11 p.m. Sundays through Thursdays and 10 a.m. to midnight Fridays and Saturdays. 275 S. Murphy Ave., Sunnyvale, and 401 San Antonio, Mountain View. shakeshack.com