Give it the Bass-o-matic treatment in a food processor, then chill and fry. salmon, tuna, amberjack, halibut and other steak-like fish would be fine substitutes for the mahi mahi. Prep time doesn't include the chilling.
Combine the fish, cilantro, hoisin, mayonnaise, green onions, ginger, garlic, salt and pepper in a food processor. Pulse until finely chopped. Pat into 4 patties. Chill for 1 to 4 hours. (Or 20 minutes in the freezer.).
Heat vegetable oil and sesame oil in a large skillet over medium heat. Add the fish burgers and cook for 3 minutes per side or until just cooked through.
Serve on toasted buns with mayonnaise and extra hoisin, topped with lettuce and tomato.