Preheat oven to 400F (200C). Toss cubed potatoes with olive oil, half the salt, and half the pepper. Roast on a baking sheet for 25 minutes until crispy.

In a small bowl, whisk together mayonnaise, ketchup, yellow mustard, and sweet pickle relish to create the dressing. Set aside in the refrigerator.

Divide the ground beef into four equal 4-ounce portions and roll them into loose balls. Heat a large cast-iron skillet over medium-high heat.

Place the beef balls in the hot skillet. Using a heavy spatula, press down firmly to flatten them into thin patties. Season with remaining salt and pepper.

Cook for 2 to 3 minutes until a dark crust forms. Flip the patties, top each with a slice of cheddar cheese, and cook for 1 more minute until melted. Remove from heat.

Assemble by dividing the chopped romaine lettuce and roasted potatoes among four dishes. Top with the cheesy patties, cherry tomatoes, red onion, and dill pickles. Drizzle with the prepared dressing before serving.