For the sauce, peel the lime so that the white skin is completely removed. Remove the fillets with a sharp knife between the parting skins. Press the juice out of the parting skins. Heat 2 tablespoons of butter in a saucepan and sauté the coriander briefly. Add the lime fillets, juice and stock, bring to the boil and reduce to about 2/3. Add cream. Finely puree the sauce with a hand blender, pour through a fine sieve, season to taste with salt and vinegar. Keep sauce warm
Cut Romanesco and cauliflower into florets from the stalk and blanch in boiling salted water for about 3 minutes. Pour into a sieve and rinse immediately in very cold water. Wash the thyme and shake dry. Fish wash, dab dry. Heat the oil in an ovenproof pan. Fry the fish for about 3 minutes while turning. Season with thyme, salt and pepper
Cook in the preheated oven (electric cooker: 100 °C/ circulating air: 75 °C/ gas: see manufacturer) for approx. 20 minutes. The fish is cooked when the meat separates easily from the middle bone. In the meantime, wash parsley, shake dry, pluck leaves from the stalks and chop. Heat 2 tablespoons of butter. Sauté the cauliflower and Romanesco for about 5 minutes. Season to taste with salt and pepper. Mix in parsley
Remove the skin from the fish, then remove the meat from the middle bone. Arrange fish, sauce and vegetables