Preheat the oven to 180°C.
Bake potatoes on a bed of rock salt for one hour.
Scrape the soft potato flesh from the skins once cooled slightly.
Boil large carrot rounds in salted water for 10 minutes, then refresh in ice water.
Mix potato, crab, and lime zest, then shape into barrels and chill in the fridge.
Coat chilled croquettes in flour, then beaten egg, and finally breadcrumbs.
Whisk butter into hot fish stock, add vermouth, and season to make the sauce.
Fry mushrooms in butter for five minutes until cooked.
Wilt the baby spinach into the mushroom mixture.
Pan-fry fish skin-side down, then bake for 5-6 minutes until cooked.
Fry the semi-cooked carrots in butter until the edges soften.
Rest the cooked fish under foil for five minutes.
Deep fry the croquettes at 190°C for five minutes until golden.
Platter the spinach and mushrooms with the fish on top.
Garnish with carrots and a croquette, served with sauce on the side.