Cook the Bacon: Cook the bacon in a large skillet over medium heat until crispy. Transfer to a paper towel-lined plate and set aside. Reserve a small amount of bacon drippings if you'd like extra flavor for the burgers.
Prepare the Beef: Divide the ground beef into 8 loosely packed balls, about 4 ounces (115g) each. Avoid compacting the meat too much, as loose beef helps create tender patties with crispy edges.
Make the Burger Sauce: In a small bowl, stir together the mayonnaise, barbecue sauce, mustard, and pickle juice until smooth. Refrigerate until ready to use.
Preheat the Cooking Surface: Heat a cast iron skillet, flat-top griddle, or griddle pan over high heat until very hot. A properly heated surface is essential for achieving the signature smash burger crust.
Smash the Burgers: Place the beef balls onto the hot surface and immediately press them into thin patties about ¼ inch thick using a burger press or sturdy spatula. Season with salt, pepper, and garlic powder, then cook undisturbed for 2 to 3 minutes.
Flip and Add Cheese: Once the edges are deeply browned and crispy, flip the patties and top each with a slice of cheddar cheese. Cook for 1 to 2 minutes more until the cheese is melted.
Toast the Buns: While the burgers finish cooking, lightly toast the brioche buns until golden brown. This helps add texture and prevents sogginess.
Assemble the Burgers: Spread the burger sauce onto the toasted buns. Layer with lettuce, tomato, red onion, pickles, two cheesy patties, crispy bacon, and an extra drizzle of barbecue sauce if desired.
Serve and Enjoy: Serve immediately while hot and fresh. You'll be rewarded with juicy smash burgers loaded with crispy edges, smoky bacon, melted cheddar, and bold barbecue flavor in every bite.