For the salmon, you can use a 500 gram (1 lb) fillet, use 4-5 smaller fillets, use leftover cooked salmon, or even canned salmon, well drained and the approximate weight stated. The salmon has to be cooked and flaked, you can bake or steam the fillets, up to you. Season with garlic salt and black pepper before cooking, if baking, brush with olive oil as well. Let the salmon cool to room temperature. Then flake the salmon with two forks and remove and discard the skin and any bones, depending on the cut you use.
In a medium skillet over medium heat, heat a tablespoon of olive oil, 1 tablespoon of butter and the onion and bell pepper. Cook until softened and starting to turn golden brown, about 6 to 8 minutes then remove from heat.
In a large bowl, and the salmon, bread crumbs, eggs, mayo, Worcestershire sauce, 1 teaspoon garlic salt, ¼ teaspoon of black pepper, and parsley. Stir to combine.
Add the onion and bell pepper, and mix that in then form into 12-14 patties. You can use either large tablespoons of the mixture or use an ice cream scoop. Flatten the portion out and form into about ½ inch thick patties.
Heat 1 tablespoon of olive oil and 1 tablespoon of butter in a large non stick skillet over medium heat and once butter is done sizzling, add half of the salmon cakes and fry for 3 to 4 min per side or until golden brown. If salmon cakes brown too quickly, reduce heat. Remove to a paper towel lined plate to drain. Add remaining oil and butter and repeat cooking remaining salmon cakes.
Serve with a tartar sauce or dipping sauces of your preference.