Place garlic, tomato puree, stock, olive oil, apple cider vinegar and spices into a slow cooker (or deep roasting tray) and combine well.
Place beef into marinade and cook in slow cooker on low for 6 hours (or cover roasting tray and cook in a slow equivalent oven) or until meat is tender and pulls apart easily. Add a pinch of good quality salt to your liking.
In final 60 minutes of cooking time, slice sweet potato into 1/2cm thick rounds and brush both sides with olive oil. Place onto a lined baking tray and bake in oven for 30 minutes each side or until golden and tender.
Meanwhile, prepare coleslaw by combining all ingredients well. Set aside in fridge until ready to serve.
Once meat is tender remove from heat and use two forks to shred meat and stir through the remaining sauce.
Assemble sliders by layering a slice of sweet potato with coleslaw, shredded meat and top with another sweet potato slice to create a burger (use short skewers to hold together if needed).