Heat a large cast-iron skillet over medium-high heat. Add the vegetable oil, then add the onion, ground beef, 1/2 teaspoon salt and a few grinds of pepper. Cook, undisturbed, until the beef starts to develop a crust, 1 to 2 minutes. Flip with a spatula, breaking up the meat. Continue cooking until browned, about 30 more seconds. Stir in the pickled peppers, then arrange the cheese over the meat mixture; remove from the heat and let melt.
Spread the mayonnaise on both sides of the rolls. Divide the beef among the roll bottoms using a spatula. Top with lettuce, tomatoes, ketchup, hot sauce and the roll tops. Serve with potato chips.