Lay the 8 strips of bacon in a cold skillet over medium heat and cook for 6 to 8 minutes, flipping once, until deep brown at the edges. Drain on paper towels and leave 1 tsp of fat in the pan.

Whisk together the 4 tbsp mayonnaise, 1 tbsp ketchup, 1 tsp yellow mustard, 1 tsp smoked paprika, and 1 tsp Worcestershire sauce in a small bowl until smooth. Set aside.

Divide the 1 lb ground beef into 4 equal portions. Press each into a 4-inch wide, 3/4-inch thick patty, make a thumb dimple in the center, and season both sides with the 1/2 tsp kosher salt and 1/2 tsp black pepper.

Heat the skillet with reserved bacon fat and 1 tbsp neutral oil over high heat until shimmering. Cook the patties 3 to 4 minutes on the first side, flip, add 1 slice American cheese to each, and cook 2 to 3 more minutes until the internal temperature reaches 160°F (71°C).

Toast the buns cut-side down in the skillet over medium heat for 1 to 2 minutes until golden. Spread sauce on both cut sides, then layer lettuce, tomato, onion, the cheese-topped patty, and 2 strips of bacon on each bottom bun. Set the top bun in place and serve immediately with extra sauce on the side.