01 - Grate the peeled potatoes using a box grater. Gather the shreds in a clean kitchen towel and wring out as much moisture as possible. Transfer the dried potato shreds to a mixing bowl.
02 - Add the melted butter, vegetable oil, garlic powder, onion powder, salt, and pepper to the grated potatoes. Toss until the seasoning is evenly distributed throughout.
03 - Heat a large nonstick skillet or griddle over medium-high heat. Divide the potato mixture into 4 equal portions. Press each portion into a thin round patty about 4 inches in diameter. Cook for 3 to 4 minutes per side until deeply golden and crisp. Remove from the pan and keep warm.
04 - Gently shape the ground beef into 4 loose balls, being careful not to overwork the meat. Heat the skillet or griddle over high heat. Once screaming hot, place the beef balls on the surface and immediately smash each one flat with a heavy-duty spatula or burger press. Season the top generously with salt and pepper.
05 - Cook the patties for 2 to 3 minutes until the bottom develops a dark crust and the edges turn crispy. Flip each patty, lay a slice of cheddar cheese on top, and cook for 1 to 2 more minutes until the cheese is fully melted.
06 - Spread burger sauce on the bottom half of each toasted bun. Layer on a lettuce leaf, a tomato slice, and a few rings of red onion. Place a hash brown patty on top, followed by the cheesy smashed burger. Add pickle slices and cap with the top bun.
07 - Serve immediately while the hash browns are still crunchy and the cheese is molten.