With a food processor: combine all patty ingredients and pulse until sticky but still slightly chunky. Without a food processor: mince garlic and shallot, grate ginger into a bowl, crush cornflakes in a bag, dice salmon finely by hand, add remaining ingredients and mash together.
Form the mixture into patties.
Heat a skillet on medium with avocado or olive oil. Sear patties 3 to 4 minutes per side until browned, then transfer to the oven for approximately 15 minutes.
While the patties cook, whisk all sauce ingredients together.
Spread sauce on a bun, add the patties with tomato, cucumber, and greens. Alternatively, serve over rice or on a salad.