Season the beef mince, shape into four patties and fry on the Tepan cooktop. Slice the shallot and carrot into fine strips. Peel, de-stone and mash the avocado and mix with the cabbage. Add the lime juice and zest and season with salt to taste. Halve the burger buns and cook on the Tepan until golden brown. Place the coleslaw and cooked patties in the buns.