Make the Special Sauce: In a small bowl, whisk together the mayonnaise, sweet pickle relish, yellow mustard, white vinegar, garlic powder, onion powder, and paprika until well combined. Taste and adjust seasonings as needed. Set aside.

Prepare the Toppings: Shred the lettuce, finely dice the white onion, and slice the dill pickles. Set aside.

Prepare the Meat: Divide the ground beef into 12 small, even portions (about 2-3 tablespoons each). Don't pack them too tightly.

Smash and Cook: Place a tortilla on a cutting board or plate. Place a portion of ground beef on the tortilla and use your fingers or a small spatula to press it into a very thin, even layer, extending it almost to the edges of the tortilla.

Sear the Meat Side: Heat a large skillet or griddle over medium-high heat. Once hot, carefully place the tortilla, meat-side down, onto the hot surface.

Cook Until Crispy: Cook for 2-3 minutes, or until the beef is browned and crispy, and the edges of the tortilla are starting to crisp up. Don't move the tortilla around too much during this time, as it needs to develop a good sear.

Flip and Add Cheese: Carefully flip the tortilla. Immediately place a slice of American cheese on top of the cooked beef.

Cook Tortilla Side: Continue to cook for 1-2 minutes, or until the cheese is melted and the tortilla is golden brown and crispy.

Remove from Heat: Remove the cooked taco from the skillet and set aside on a plate or wire rack.

Repeat: Repeat steps 4-9 with the remaining tortillas and ground beef.

Add Toppings: Spread a generous amount of the special sauce on the cheese. Top with shredded lettuce, diced onion, and pickle slices.

Serve Immediately: Serve the Big Mac Smash Tacos immediately while they're hot and crispy.