Preheat a cast iron skillet on high. Using a pad of butter, toast your burger buns in the skillet until golden brown. Set buns aside somewhere warm.
Wipe out any remaining butter or debris from the cast iron skillet and preheat 2 tbsp of high smoke point neutral oil (canola, grapeseed, avocado) in the cast iron on high heat.
Season one side of patties with salt and pepper and place the seasoned side down in the cast iron. Now season the side facing up with salt and pepper then press down with a spatula. cook on side 1 for about 90 seconds total, then flip.
Add the cheese to each patty, and cook on 2nd side for another 30 seconds. Once the cheese is fully melted and the burgers are fully cooked, assemble your burgers. 2 patties per burger.
Assemble each burger with bottom bun, lettuce, shallot, 2 patties, pickles, sauce and top bun in that order.