Place lamb mince in a large bowl and season with salt and pepper. Using damp hands form 4 patties, pressing down on pattie with the back of your hand to flatten.
Preheat a large non-stick frying pan or BBQ over medium-high heat. Rub patties on both sides with oil. Cook patties for 2-3 minutes or until bottoms are lightly charred. Turn patties over and top with cheese.
Cook for a further 2 minutes, or until bottoms are lightly charred and cheese has melted. Set patties aside on plate loosely covered with foil.
In a small bowl place onion and vinegar. Season with salt and toss to coat.
Spread tzatziki over bottom halves of buns. Top with baby cos, lamb patties, tomato, beetroot and drained pickled onion. Top with mint sprigs and serve.
Tips
This is a great recipe for feeding a crowd – you can simply cook the burgers and lay them our with all the other ingredients for people to build their own burgers.
