The mixture needs to refrigerate at least 2 hours. You can make the up to 8 hours ahead of time before cooking. We made the mixture about 6 hours ahead of time, if you have the time to make ahead, it gives the flavors time to meld.
Put the chopped salmon in a food processor and pulse about 6 times, just until it is finely chopped. You still want the texture to have some chunks not a paste.
(we used a mini food processor and worked in batches)
Put the yogurt, scallions, dill, both mustards, lemon juice and lemon zest in a large bowl and stir to blend. Gently stir in the salmon until the ingredients are combined then season with the salt.
Cover the bowl, pressing a piece of plastic wrap against the surface of the mix, and refrigerate for at least 2 hours.
(the burger mix can be refrigerated for up to 8 hours.)
When you’re ready to make the burgers, divide the salmon into 6 portions and shape each one into a patty.
Use heavy duty aluminum foil and brush the foil with Canola or Vegetable oil. This will prevent the burgers from sticking and you will still have the smokiness from the grill.
Use just enough Canola or Vegetable oil to lightly coat the bottom of the pan.
If you have enough room on your grill, you can cook all six burgers at the same time. If cooking in the skillet, you might need to cook in two batches. Cook the burgers about 3-4 minutes on each side, you want the burger to be firm before flipping. These are delicate until cooked.
Serve immediately, sandwiching the burgers between the buns and topping them with your favorite toppings.