Pickled Salmon

This recipe is a reworking of a very old family recipe. My mother-in-law used to soak lox–also known as smoked salmon–in water for days to remove the salt, then put it in pickling brine. As we can get great local salmon, I tried it for this dish, and it has become a much-requested favorite. The onions are not just a visual garnish. They pick up the flavor of the marinade and are a delicious counterpoint to the salmon. Serve with rye bread or, at Passover, with matzo.