Step 1

Preheat a griddle or large frying pan until hot and brush with the vegetable oil.

Step 2

Form the beef mince into 4 patties and sprinkle on both sides with the salt and pepper.

Step 3

Place the patties on the griddle and cook, for about 3 minutes, until browned, then turn the burgers over and place a slice of cheese on top of each burger.

Step 4

Cook for a further 1-3 minutes, until the burger is cooked through.

Step 5

Take the burgers off the griddle when cooked and leave to rest for 2-3 minutes.

Step 6

Whilst the burgers are resting, mix the sauce ingredients together and put to one side.

Step 7

To assemble the burgers. Place the lettuce on the bottom of two of the burger buns followed by slices of tomato. Add a burger to each bun.

Step 8

Top with onion slices and another burger.

Step 9

Drizzle over the sauce and place the top of the bun on each burger and serve.