In a large bowl, gently mix the ground beef with kosher salt and black pepper until just combined. Divide into six portions and shape each into a patty about 1 inch thick.

Heat the skillet over medium-high heat and add a drizzle of canola oil, allowing it to heat for about 2 minutes.

Add the beef patties to the hot skillet and cook for about 3-5 minutes on the first side. Flip and cook for another 3-5 minutes until desired doneness, adding cheese in the last minute.

Whisk together mayonnaise, ketchup, dill pickle relish, and Dijon mustard in a small bowl until smooth.

Cut the brioche hamburger buns in half and toast cut side down in the skillet for the last minute of cooking.

Assemble the burgers by placing a patty on each toasted bun, adding a dollop of burger sauce, and topping with lettuce, tomato, onion, and dill pickles.

Serve immediately while still warm and juicy.