Season the ground beef with salt and pepper, then divide it into eight equal portions and roll each into a ball.
Press each portion of beef onto a flour tortilla, spreading it out evenly to form a thin layer.
Warm a skillet over medium-high heat and add a small amount of cooking oil to prevent sticking.
Place a tortilla in the skillet with the beef side down, then use a spatula to press the meat firmly into the pan. Cook for about 1½ to 2 minutes, until browned.
Flip the tortilla so the cooked beef is facing up, then immediately sprinkle shredded mozzarella cheese over the patty. Cover the skillet and cook for another 1½ to 2 minutes, allowing the cheese to melt.
Transfer the taco to a plate and repeat with the remaining portions.
In a small bowl, whisk together the mayonnaise, dill pickle relish, Dijon mustard, white vinegar, paprika, onion powder, and garlic powder until smooth.
Add the lettuce, onions, and sauce.
Fold the tortillas, and serve while warm.