Grind your own minced meat! - Or ask the butcher. Make sure it is not too coarse, so you could grind it again. The big secret to making minced meat super tasty is to add bone marrow. So take the marrow from the (briefly warmed) bones and chop it finely. Knead the marrow through the minced meat, so that it becomes smooth and binding. Knead a little longer if the burgers fall apart. Season with plenty of salt and black pepper, make burgers of 150 grams each and let them rest for a while. Cut open the brioche buns and spread them lightly with butter. Cook the burgers on the grill of The Bastard until they reach a core temperature of 55-58 °C, turning them over once. Remove the burgers from the grill and let them rest for a while. Briefly grill the buns, without burning them. Serve the buns with the meat.