Mix mayonnaise, ketchup, and sweet pickle relish in a small bowl to create the special sauce. Set aside.

Divide the ground beef into 8 equal portions. Place one portion onto each corn tortilla and press the meat flat to cover the surface evenly. Season with salt and black pepper.

Heat a large skillet over medium-high heat. Place the tortillas meat-side down and press firmly with a spatula. Cook for 3 minutes until the beef is browned and crispy.

Flip the tortillas, place a sprinkle of cheddar cheese on the beef, and cook for 1 more minute until the cheese melts and the tortilla is slightly crispy.

Remove from the skillet and top with shredded lettuce, diced white onion, chopped dill pickles, and a generous drizzle of the special sauce. Serve immediately.