Make the burger sauce

• Mix the light mayonnaise, yellow mustard, pickle juice, white vinegar and gherkin relish in a bowl.
• Season with smoked paprika, garlic powder and onion powder and stir until smooth.

Season the beef

• Put the extra lean beef mince in a bowl and season with pepper, garlic powder, onion powder, smoked paprika and salt.
• Add half of the diced white onion and mix everything together.
• Form the mixture into 4 even balls.

Press the meat onto the tortillas

• Lay the mini tortillas out and press one portion of beef onto each one, spreading it as thinly and evenly as possible.

Cook the smash burger tacos

• Cook the tortillas meat-side down in a hot pan on high heat, pressing down on them.
• Flip them over so the bottom crisps up.

Add the cheese

• Place a slice of cheddar cheese on each taco and let it melt.

Top and serve

• Top each taco with shredded lettuce, the remaining diced onion, sliced pickles and burger sauce.
• Serve immediately.