Divide the ground beef into 4 equal portions (about 5 oz each). Gently form each portion into a loose ball, then flatten into 3/4-inch-thick patties slightly wider than the buns. Do not overwork the meat.

Season

Season both sides of each patty with kosher salt, black pepper, and garlic powder just before cooking.

Cook

Heat a cast-iron skillet or griddle over medium-high heat and add 1 tablespoon vegetable oil. When shimmering, place the patties on the hot surface. Cook for 3-4 minutes on the first side without pressing. Flip and cook 2-3 minutes for medium, or longer to desired doneness. In the last minute of cooking, lay one slice of Havarti on each patty and cover the pan briefly (30–60 seconds) to melt the cheese.

Slab Sauce

While the patties cook, whisk together mayonnaise, BBQ sauce, Dijon mustard, hot sauce (if using), apple cider vinegar, smoked paprika, and black pepper in a small bowl until smooth. Taste and adjust sweetness or heat. Keep chilled until assembly.

BBQ Back Rib Meat

If you have pre-cooked BBQ back ribs, remove the meat from the bones and shred it finely using two forks. If the meat is dry, warm it gently in a small saucepan with 1–2 tablespoons of BBQ sauce until moist and heated through. Keep warm.

Quick Pickled Onions (optional)

Combine 1 tablespoon apple cider vinegar, 1 tablespoon water, 1/4 teaspoon sugar, and 1/8 teaspoon salt in a small bowl. Add thinly sliced red onion and let sit at least 10 minutes (or refrigerate up to 1 hour) to quick-pickle. Drain before using.

Buns & Assembly

Toast the buns: Spread softened butter on cut sides of the buns. In a clean skillet over medium heat, toast buttered sides until golden, about 1–2 minutes.

Assemble each burger: Spread about 1 tablespoon of Slab Sauce on the bottom bun. Place the Havarti-topped patty on the sauce. Pile about 1/4 cup shredded BBQ rib meat on top of the cheese. Add a few dill pickle slices and approximately 1/4 cup onion straws. If using pickled red onion, add a little. Drizzle another teaspoon of Slab Sauce on the top bun, then close the burger.

Serve immediately with extra Slab Sauce on the side.