Blend dried mushrooms into a powder and combine with pepper and herbs.
Slice duck breasts lengthways into 3mm thick slices.
Slice three courgettes into thin strips using a vegetable peeler.
Stack duck slices into six portions, alternating layers of fat and lean meat.
Place courgette strips over duck portions and season with mushroom powder and salt.
Roll the layers tightly into cylinders and secure with kitchen string.
Repeat the process to create six individual tournedos.
Grill the rolls on a barbecue or griddle for 5 minutes per side.
Dice remaining courgettes and mix with onion, mint, lemon juice, and oil.
Slice the tournedos thickly and serve with the courgette salad.