In a small saucepan combine golden mushroom soup, Worcestershire sauce, and slices mushrooms. Heat over medium heat until simmering.
In a small bowl mix seasoned salt and pepper. From the ground beef into 4 patties. Season on both sides with the seasoning mixture.
Lightly grease the grates of an outdoor grill. Heat to medium-high heat. Add the beef patties, and grill for about 5 minutes per side or until fully cooked (the internal temperature has reached 160 degrees F.). During the last few minutes of cooking top each patty with a slice of swiss cheese. Grill until the cheese has melted. Remove from the grill.
Split the hamburger buns and toast them cut side down on the grill until lightly browned.
Place the burger patties on a bun. Top with mushroom sauce. Spread mayonnaise until the bottom of the top half of each bun and place on top of the burger.