beef, garlic, thyme and some salt and pepper in the bowl and
work together with your hands until evenly mixed and slightly
sticky. Divide into 4 portions and shape into patties. Cover and
chill for 30 min.
Brush the patties lightly with olive oil and barbecue or grill for 5
minutes on each side until lightly charred and cooked through. Top the
patties with the cheese slices set under a hot grill for 30 seconds
until the cheese has melted. Keep them warm.
Toast the buns, then spread each base and top with mayonnaise. Add the
lettuce leaves, cheese-topped patties and tomato and onion sliced. Add
the bun tops and serve hot.