Raw tuna or salmon? Brown rice or white? Spicy mayo or ponzu sauce? Options reign at downtown Mountain View's Poké Bar, but don't worry, you'll have time to ponder what to order in line -- because there's usually a line and it's a long one.

Poké (pronounced poke-ay) is a beloved Hawaiian staple of cubed, seasoned raw fish, mixed as a free-form salad with various add-ins. In Hawaii, it can be found everywhere from grocery stores to gas stations.

The raw fish salad certainly isn't a new creation, but lately, versions have popped up on the mainland -- not only at restaurants, but also at fast-casual eateries dedicated to the dish. Locally, there's Poké Bar, which opened inside Ava's Downtown Market & Deli on Castro Street last November. Another fast-casual poké restaurant is set to open down the street in April.

Why is the latest lunch option blowing up? It's fast and healthy, Poké Bar co-owner Chris Lim said.

"Everyone is thinking about health more than taste and money," Lim said. "People want something healthy and poké happens to be healthy, light and fast."

Poké Bar operates four locations in Southern California, with a fifth currently under construction. The Mountain View location, which is more like a deli counter than a storefront, is the first in Northern California, with another on the way to San Francisco's Twitter building.

Lim found the location in Ava's by chance, he said. After his real estate agent couldn't find a suitable location on Castro Street, Lim drove up from Southern California and walked up and down the busy downtown street.

"I passed by this market and saw that nothing much was going on in the space, so I went inside and talked to the owner of the market and asked him if the space was available and told him about my poké business in Los Angeles," Lim said. "He didn't know what poké was and I started talking to him and we kind of connected."

Lim and his two business partners, Jason Park and Yoon Ju, were able to secure the 220-square-foot space and transformed it into a build-your-own poké joint, similar to a Chipotle for deconstructed sushi.

On any given weekday around lunchtime, a crowd of hungry customers pack into the small space, moving in a cafeteria-style line along the poké bar (hence the name). On a wall behind the counter are orange and white signs with ordering instructions.

For $9.50 you can get a small bowl with two scoops of bite-size pieces of fresh fish, which is the most important ingredient in a poké bowl, Lim said. Poké Bar's fish comes directly from Hawaii, Canada, Norway and the Philippines.

"We sell so much, so we don't have to keep fish in the freezer," Lim said. "We rotate really fast so it stays fresh."

Poké Bar offers a variety of poké, including tuna, salmon, seared albacore, spicy tuna, octopus, shrimp, scallop and tofu. There are various mix-ins, like cucumbers, onions, corn and jalapeño, and five housemade sauces (house dressing, ponzu, spicy mayo, sweet chili and wasabi mayo) for customers to mix and match to their pleasing.

A server mixes the delicate fish and fixings together in a metal bowl and places the poké atop a base of brown or white rice, spring salad or tortilla chips and garnishes with sesame seeds or crispy onions.

Don't know what to order? Lim's go-to is tuna and salmon mixed with cucumbers, cilantro, green onions and edamame (soy beans) with a mixture of the house dressing -- a soy-based Japanese mustard with sesame oil and other ingredients he wouldn't divulge -- and ponzu, a tangy soy-based sauce, all topped with masago (fish roe).

"The ponzu gives the bowl a citrus taste and the house dressing has the savory mustard flavor that goes perfectly with the fresh salmon and tuna," he said. "I also just like the texture of the bowl."

For a vegetarian option that keeps the same flavors and accoutrements, Lim recommends replacing the salmon and tuna with tofu and vegetables.

The salmon and spicy tuna poké are refreshing and bright, heaped atop steamed rice with the added crunch from a generous sprinkling of sesame and masago. The spicy tuna and sauces (try the spicy mayo and ponzu) add a touch of heat. Diced mango and sliced cucumbers balance the bowl out in both flavor and texture.

Customers can dine at small tables inside or outside the market, but it is best to take your meal to go, as the few tables available will likely be occupied at peak hours.

The poké trend, like any food trend, may fade, but Lim said he is confident that poké will eventually become a California staple.

"Poké, I think, is here to stay because it's just more fitting to everybody," he said. "You don't need to wait for a sushi chef to roll your fish. With a poké bowl, you get everything you like and the only things that you like."

Poké Bar

340 Castro St., Mountain View

415-967-9728

ilovepokebar.com

Hours: Daily, 11:30 a.m. to 8 p.m.