01 - Set a large skillet or griddle over medium-high heat. Add 1 tbsp unsalted butter and allow it to melt completely across the cooking surface.
02 - Add the ground beef to the skillet, spreading it into an even layer. Press down firmly with a spatula to achieve a classic smash burger crust. Let it cook undisturbed for 2 to 3 minutes until a deep brown sear forms, then break the meat apart into crumbles.
03 - Stir in the finely diced onion and cook for 3 to 4 minutes until softened and translucent. Add the minced garlic and continue cooking for 1 additional minute until fragrant.
04 - Add the chopped dill pickles, ketchup, yellow mustard, Worcestershire sauce, brown sugar, smoked paprika, black pepper, and salt. Stir thoroughly to combine and let the mixture simmer for 5 to 7 minutes until thick, glossy, and saucy.
05 - While the meat simmers, butter the cut sides of each hamburger bun. Place them face-down on a separate pan or griddle over medium heat and toast until golden brown and crisp.
06 - Lay the cheese slices directly over the hot beef mixture. Allow the residual heat to soften and slightly melt the cheese, then remove the skillet from heat.
07 - Spoon a generous portion of the cheesy beef mixture onto the bottom half of each toasted bun. Top with sliced tomato and shredded lettuce if desired, then cap with the top bun. Serve immediately while hot.