Rinse, gut and fillet the mackerel.
Prepare the marinade by combining the olive oil, Mazzetti Prosecco Wine Vinegar, dill and Sichuan peppercorns. Place the mackerel fillets in a small baking dish and cover them with the marinade. Leave to rest for 30 minutes.
Wash the vegetables, then peel and slice the carrots into ribbons with the aid of a peeler, cut the radishes into rounds and the celery stalk into diamond shapes.
After the marinating time has elapsed, remove the mackerel fillets and cut them crosswise into oblique slices.
Combine all the vegetables in a bowl and season with 3 tablespoons of soy sauce, pepper, olive oil and a little sesame oil. Season with salt if necessary.
Place a portion of the dressed salad on the serving plate and place the two marinated and cut mackerel fillets on it, skin side up. Sprinkle with sesame seeds and serve.