Defrost required number of burgers. Finely shred red onion, carrots & cabbage and combine. Heat rice vinegar & sugar until sugar dissolves and pour over slaw mix and leave to one side to pickle. Meanwhile begin cooking burgers. Lay in a hot griddle pan and cook as per packet instructions. Top with vegan cheese slices and melt gently under a hot grill. Build the burger starting with bun base topped with lettuce and sliced tomato. Add the burgers, another layer of lettuce and slaw mix. Spread vegan mayo over bun lid and place on burger stack. Serve with crispy stealth fries.