Rinse fish, dry and sprinkle with juice of one lemon. Season with salt and pepper, place in a lightly oiled ovenproof dish.
Clean the leeks, rinse and blanch them, undivided, briefly in boiling hot salted water. Cut the drained leek into finger-thick rings and place in the mold with the fish.
Drizzle fish and leek with oil. Mix soy sauce with rice wine and pour a third of the liquid over the fish form. Place in the oven and bake for 40 minutes at 225 °C (not preheated). Pour the sauce over the fish a few times.
Serve with grainy cooked long grain rice or simply baguette. **