Step 1
To make the tomato chilli relish, heat the oil in a medium saucepan over medium heat. Add the onion, garlic and chilli and cook, stirring, for 5 mins or until onion softens. Add the tomato and cook, stirring occasionally, for 5 mins or until tomato softens. Stir in the sugar and vinegar and cook, stirring occasionally, for 10 mins or until thickened. Season. Set aside to cool.
Step 2
Heat the oil on a barbecue grill or chargrill on medium heat (alternatively, heat the oil in a large frying pan over medium heat). Cook the burger patties for 5 mins or until browned underneath. Turn and cook for a further 5 mins, topping each patty with a cheese slice for the last 2 mins of the cooking time, or until golden and cooked through.
Step 3
3 Place roll bases on serving plates. Top with lettuce, patties, beetroot, pickles and tomato chilli relish. Top with the roll tops to serve.