01 - Preheat a large skillet over medium heat. Add ground beef and cook, breaking it into crumbles, until browned, about 4 minutes.
02 - Add diced onion and minced garlic to the pan. Continue cooking until the onion is translucent and garlic fragrant, around 2 to 3 minutes.
03 - Stir in salt, black pepper, ketchup, yellow mustard, and Worcestershire sauce. Cook for an additional 1 to 2 minutes, then remove from heat and set aside to cool briefly.
04 - Spread softened butter on one side of each bread slice. Set aside for assembly.
05 - On the unbuttered side of four bread slices, place one slice of cheddar, spoon over beef mixture, then add pickles, tomato, and lettuce as desired. Top with another slice of cheddar cheese.
06 - Cover each prepared stack with a second bread slice, ensuring the buttered side faces outward.
07 - Heat a clean skillet over medium-low. Add sandwiches and cook for 3 to 4 minutes per side, gently pressing, until bread is crisp and golden and cheese has melted.
08 - Transfer sandwiches to a cutting board, allow to rest for 1 minute, then slice and serve hot.