Vacuum the fillet of beef and let it rest for 10-15 minutes at room temperature. Heat the water to 56 ° C and place the fillet in a water bath at the same temperature. Cook in a water bath for about 50 - 55 minutes.
Meanwhile, bake the bread according to the instructions on the packet.
Prepare the pesto - mix rocket, pine nuts, parmesan and oil until you get a creamy mixture. Cut the mozzarella and tomatoes into small cubes.
Cut the bread into slices and brush with the pesto. Place the tomato and mozzarella pieces on the coated slices.
Heat a pan and sear the fillet steak in it. Serve sprinkled with salt and pepper.