Shape ground beef into 3 thick patties, trying not to pack too much. Heat skillet over medium high heat. When skillet is very hot, sprinkle salt in the skillet and cook patties for 3 minutes on each side, or until done as desired. Meanwhile, in a small bowl, combine mayonnaise, ketchup, and relish. Spread a little mayonnaise mixture on each bun. Top with hamburger patties, tomato slice, and onion slice. Serve with dill pickle slices. Serves 3. If you use leaner beef, the burgers might be a bit dry.