Pickled Red Onion:
Pickle the onions by tossing with the seasoning (or salt and pepper) and yuzu (or lime) juice; let stand.
Pulse the tuna in a food processor to chop finely, then gently combine with the other patty ingredients. Form 4 patties and coat with oil.
Heat a griddle or nonstick skillet over medium-high heat. In a small bowl, combine the sauce ingredients.
Cook the burgers for 4 to 5 minutes for pink centers and 7 to 8 minutes to cook through, turning once.
Serve the burgers on the toasted buns topped with pickled onions, toasted nori, pickled ginger and the special sauce.
In a round-bottom pan or wok, heat the oil over high heat. Add the edamame and sear to brown the pods at the edges. Add the garlic and ginger and stir-fry for 1 minute. Add the ponzu (or tamari), honey (or agave), sriracha, sesame oil and seeds. Toss to combine and serve hot as a side dish or starter.