To make the Beet Slaw whisk together the oil and vinegar in a medium bowl. Add apple, carrot, beetroot, mint, rocket leaves and toss to combine. Season with salt and pepper.
To make the Mayo Relish whisk mayonnaise, tomato sauce and onion relish in a medium bowl.
Preheat grill on high. Mix the mince, BBQ sauce, tomato sauce, salt and pepper together in a bowl. Shape the mince into 10 x 150g sized balls. Heat a large heavy frying pan over high heat. Add 2 mince balls to the pan and, using a sturdy spatula, immediately press on mince balls to flatten into about 1cm-thick patties. Cook for 2 mins or until base is browned and crisp. Turn patties and cook for a further 2 mins, or until browned and cooked through. Transfer patties to a large baking tray. Repeat to cook remaining mince balls..
Spread bun bases with Mayo Relish and place patties on bun bases. Place 1 slice of pineapple on each patty, top with Beet Slaw and cover with bun top. Serve with chips and extra Mayo Relish.
Tip: Replace the minced patty with chicken breast for a ‘customised’ variation.