Method

• 1.
  Place one John Dory in the centre of a cutting board and begin to scissor the fins from the top of the fish and from the collars on both sides. Using a large chef’s knife, cut the head and collars off the fish in one piece, then draw the blade down from behind the head to the belly flap which sits alongside the collar. Do this on the other side as well, so the cuts meet up at the top of the fish. Using your hands, break the spine so the head and collars separate cleanly away from the rest of the fish. Repeat with remaining John Dory.
• 2.
  To make the gremolata, combine eel, lemon zest and juice, garlic, horseradish and olive oil in a bowl. Season to taste with salt flakes and freshly ground black pepper and set aside.
• 3.
  Heat a charcoal grill to high. Make sure the grill is hot and the charcoal has cooked down to hot embers. Divide coals across the floor of the charcoal grill to create a cooler side and a more intense side. When you’re ready to cook the fish, brush the skin of the body and the collar and head section with a little grapeseed oil and season liberally with salt flakes.
• 4.
  Depending on the size of your charcoal grill, you may need to cook the fish in batches. Place the head and body directly on a wire cake rack sitting on top of the grill bars over a high heat. By working on a cake rack, you will have the ability to move the fish on and off the heat.
• 5.
  Cook both pieces for about 2 minutes on each side or until nicely coloured, then move them both to the cooler side of the grill. Cook the head and collars for another 8-10 minutes, turning every 2-3 minutes, until the meat surrounding the head and collars has just set. Cook the body, turning as per the collars, for another 5-10 minutes, until cooked through, or until the flesh flakes when tested with a fork. Remove from the heat and transfer to a wire rack set over a tray to rest.
• 6.
  While the fish is resting, stir the parsley through the gremolata.
• 7.
  To assemble the dish, position the John Dory body, head and collars onto small serving dishes. Spoon the gremolata over the top and serve with the watercress alongside.