This classic fish sandwich is a mainstay on hawaiian menus, where it is often listed as a fish burger. The best one i ever had was from a lunch truck in the parking lot of a fish storethe kind of fish store right near the pier and the fish comes in, gets cleaned and put on ice in the counter within minutes, and eager customers show up early in the day lest their favorite sells out. Both the store and the truck had a lovely ocean view. I've modeled this recipe off that sandwich, but have experienced first-hand with this recipe what is always true about fish dishes: the fresher the fish, the tastier it will be. In hawaii, these sandwiches are usually made with mahi-mahi (a. K. A. Dorado) or ono, both of which are ocean fish with firm flesh and lots of flavors that give the "Burger" A great meaty feel. Another firm white fish, like farmed tilapia, makes a perfectly tasty burger where and when mahi-mahi isn't available. Would this burger also work with salmon? Absolutely. Freshness and a certain thickness of the filet to stand up to the bun are all this sandwich require.