Preheat a grill or skillet over medium-high heat.
In a bowl, mix the ground beef with Tony Chachere’s Original Creole Seasoning until well combined. Form into 4 equal patties.
In a skillet, heat olive oil over medium heat. Add sliced onions and sauté until caramelized, about 10 minutes. Stir occasionally to prevent burning.
Cook the beef patties on the grill or skillet for about 4-5 minutes on each side, or until they reach your desired doneness. During the last minute of cooking, place 1 slice of cheddar and 1 slice of Swiss cheese on each patty to melt.
Toast the hamburger buns on the grill or in a toaster until golden brown.
Assemble the burgers by placing a patty with melted cheese on the bottom half of each bun. Top with caramelized onions, lettuce, tomato slices, and pickles. Place the top half of the bun on each burger.
Serve immediately and enjoy!