Over medium heat, sauté red onion for 6 minutes and set aside to cool.
Finely chop the salmon and place in to a mixing bowl.
Add all ingredients and blend well. Adjust panko so it binds the mixture together.
Pour 1 /4 the mixture in to a medium high skillet and form in to a patty with a utensil. Cook for 4-5 minutes per side or until center is just shy of raw.
Serve over arugula dressed with fine olive oil and fresh orange juice.