Beef burger with pastrami

Ingredients:

• 350 grams of quality pastrami, chopped
• 0.9 kg ground beef (20% fat)
• 55 g (1/4 cup) unsalted butter
• 2 cloves garlic, crushed
• 1/4 cup canola oil
• 1 onion, thinly sliced
• 8 slices of Muenster
• 4 soft brioche hamburger buns, cut in half horizontally
• 2 pickled cucumbers, thinly sliced
• 8 Boston lettuce leaves (about 1 small head)
• 2 heirloom tomatoes, thinly sliced
• Cumin Coleslaw

Preparation:

1. Build a fire and wait until the flames die down, until the coals are red and covered with white ash. Lower the grill grate over the coals, and you'll have a good, even medium, heat.
2. Place the butter and garlic in a large cast-iron skillet and heat over medium heat (or on the stovetop over medium heat). As the butter melts, the garlic will release its aroma. Stir well and season with salt and black pepper. Transfer the garlic butter to a small bowl and set aside to cool.
3. Return the same pan to medium heat to heat. Add enough canola oil to coat the bottom, about 2 tablespoons, then add the onion. Cook over medium heat, stirring occasionally, until the onion is caramelized, 10-15 minutes. Season with salt and cook until soft and evenly golden, about 3 minutes. Transfer the onion to a plate.
4. Increase the heat to medium-high, moving the pan so it's directly over the coals or lowering the grate so it's closer to the coals. Add enough canola oil to coat the pan, about 2 tablespoons. Add the pastrami and cook, turning several times, until crisp, 7-8 minutes. Remove the pastrami, reserving any rendered juices in the pan.
5. Divide the minced meat into 4 portions and form into 4 tight balls. Season with salt and black pepper. Place the meatballs in the skillet and fry for 30-40 seconds, then flatten them with a heavy-duty metal spatula. Continue pressing with the spatula and frying until the patties are crispy on the bottom, about 2.5 minutes.
6. Flip and cook until crispy on the other side, 1 minute. Spoon the rendered fat from the pan over the patties.
7. Top each patty with two slices of cheese. Pour 1 tablespoon of water into the skillet and cover with a lid, aluminum foil, or another pan to steam the patties (this will help melt the cheese). Let them sit, covered, for 30-40 seconds, until the cheese melts, then remove the lid. When the patties are cooked to the desired doneness and the cheese is melted, top each patty with a mound of fried pastrami, then set them aside.
8. Lightly brush the cut sides of the buns with garlic oil. Toast them directly on the grill over a campfire until golden brown and crispy around the edges, 15-20 seconds. Flip and lightly toast the outsides for another 15 seconds.
9. Assemble each burger by placing slices on the bottom half of the bun. pickled cucumbers, caramelized onions, and then a pastrami patty. Top each serving with lettuce, tomatoes, and the top half of the bun. Serve with caraway-infused coleslaw.