Make the special sauce

• Combine the mayo, onion powder, garlic powder, paprika, mustard, pickle relish and white vinegar in a bowl.
• Stir until smooth and set aside.

Press the beef onto the tortillas

• Halve the beef mince and roll into balls.
• Press one ball of beef onto each tortilla into an even, smooth layer.
• Sprinkle diced onion on top and press it into the meat, then season with salt and black pepper.

Cook the tacos

• Heat a non-stick frying pan on high heat and spray with a little oil.
• Place the tortillas meat-side down and press firmly for good contact with the pan.
• Flip, add a slice of cheese to each and cook until the meat is cooked through without burning the tortilla.

Assemble and serve

• Place the tacos tortilla-side down and top with shredded lettuce, special sauce, extra diced pickles and onion.
• Sprinkle with sesame seeds and serve.