Start by heating 2 tablespoons of olive oil in a large skillet over medium heat. Add the 3 minced cloves of garlic and sauté until fragrant, which takes about 30 seconds. Stir in a pinch of hot pepper flakes and cook for another 15 seconds to release their flavor without burning.

Next, add the chopped broccoli rabe to the skillet. Stir everything together in the hot oil until the greens begin to wilt, usually within 1 to 2 minutes. Pour in about ½ cup of water to create steam, then partially cover the skillet with a lid. Let it simmer on medium heat for around 10 minutes, or until the broccoli rabe is tender and mostly cooked through.​

Remove the lid, season with salt and pepper to taste, and crank the heat to high. Cook uncovered, stirring occasionally, until any remaining liquid evaporates completely, about 3 to 5 minutes. This step ensures the broccoli rabe is not watery when added to the burgers later. Transfer the cooked greens to a plate and set aside to cool slightly.​

In a large mixing bowl, combine 1 lb of ground turkey and 1 lb of spicy pork sausage with casings removed. Sprinkle in 1 tablespoon of salt-free steak seasoning and a bit of salt to taste. Use your hands or a sturdy spoon to mix gently but thoroughly, ensuring the sausage fat distributes evenly for juicy results. Avoid overmixing to prevent tough patties.​

Divide the mixture into 6 equal portions. Form each into a patty about ½-inch thick, making the center slightly thinner than the edges. This technique prevents the burgers from puffing up in the middle during cooking, ensuring even doneness. Place the patties on a plate, cover with plastic wrap, and refrigerate for 10 to 15 minutes if time allows; this helps them hold shape on the grill.​

Preheat your grill to medium-low to medium heat. Close the lid and let it heat for a full 10 minutes to ensure even cooking temperatures. Oil the grates lightly with a paper towel dipped in oil to prevent sticking.​

Place the 6 patties on the grill. Close the lid immediately and cook for 6 to 7 minutes on the first side. Flip carefully with a spatula, then cook another 6 to 7 minutes on the second side, or until the internal temperature reaches 165°F for safe consumption of the pork sausage. Check doneness by pressing gently; juices should run clear.​

When the burgers have about 2 minutes left on their final side, distribute the prepared broccoli rabe evenly over each patty. Top each with a slice of sharp provolone cheese, piling it right on the greens. Close the grill lid to trap heat and melt the cheese until bubbly and golden, about 1 to 2 minutes.​

While the toppings melt, split the 6 Kaiser rolls or burger buns and lightly grill them cut-side down for 1 minute until toasted and warm. This adds crunch and prevents sogginess from the juicy fillings.

Remove the topped burgers from the grill and let them rest for 2 to 3 minutes. This allows juices to redistribute for maximum flavor. Place each burger on a toasted roll bottom.​

Add the top bun and serve immediately. These burgers shine hot off the grill, with the spicy sausage, earthy broccoli rabe, and tangy provolone creating a perfect bite. Garnish with extra hot pepper flakes if desired for heat lovers.