Prepare the Salmon Mixture : In a large bowl, combine the drained salmon, bread crumbs, chopped onion, and bell pepper (if using).
Bind the Ingredients : Add mayonnaise, beaten egg, Dijon mustard (if desired), lemon juice, garlic powder, salt, and black pepper. Mix thoroughly until well combined.
Form the Patties : Divide the mixture into 6-8 equal portions and shape them into compact patties about 1/2-inch thick.
Heat the Pan : Heat the vegetable oil or butter in a large skillet over medium heat until hot but not smoking.
Cook the Salmon Cakes : Place the patties into the skillet and cook for 3-4 minutes on each side, or until golden brown and crisp. Avoid overcrowding the pan.
Serve and Enjoy : Remove the patties from the skillet and drain on paper towels. Serve warm with your favorite dipping sauce, lemon wedges, or a fresh salad.