Cut veal into cubes and freeze for about 30 minutes. Then grind with onions and sage in a meat grinder TRANSFORMA® with the coarse disc.
Form the mixture into patties using a hamburger press PÄTTI and fry in a pan until pink on both sides, about 3-4 minutes.
Season with salt and pepper.
Roast Parma ham in a pan until crispy. Cut basil into strips and mix with mayonnaise.
Cut ciabatta rolls in half and toast cut sides in pan, spread with basil mayonnaise, top with arugula and sun-dried tomatoes. Place pattie and ketchup on top. Place Parma ham on top and shave Parmesan on top.
Cover with top half and secure with a burger skewer.