Cut the salmon into pieces and freeze for about 20 minutes. Pass the chilled salmon through the coarse setting of a meat grinder.
Season the ground salmon with salt, pepper, and chives, then mix to combine. Form the salmon into 3 equal-sized patties and lightly brush them with canola oil.
Preheat a grill or grill pan to high. Grill the salmon for 3 to 4 minutes, then flip and cook for another 2 minutes.
To assemble the burgers, spread some of the avocado aioli on the bottom bun, then top with a patty, a few slices of red onion, a handful of greens, and the top bun.
Avocado Aioli
Scoop the flesh of the avocado and add it, along with all remaining ingredients ,into a blender or food processor. Blend until smooth.
Check for seasoning. Note: You can keep the seeds in the serrano if you want it to be spicier.