Season the beef with salt and pepper, divide into four portions and shape into a flat burger. Fry in oil in a large frying pan.

Peel the onion, cut into strips, sauté in olive oil and season.

Heat the BBQ sauce gently in a pan and season to taste with the Schierker Feuerstein and crushed pepper.

Cut the buns open, crisp them up briefly in a toaster or under the grill in the oven, spread the insides with mustard and burger sauce.

Place the fried meat on the bottom of the bun. Place the tomatoes and cucumber slices on top and season with salt and pepper. Then place the onions on top of the tomatoes and the BBQ sauce over the onions, place the rocket on top of the onions and cover with the top half of the bun. Serve with potato wedges or chips.