Cod:
Mix the ingredients for the marinade in a bowl and marinate the fish for an hour. Heat oil in a sauté pan, place the fish skin side down and cook on medium heat until seared. Flip the fish over, add butter and cook the other side for a further 2 minutes. Remove the fish from the pan and place on a baking tray. Apply the remaining marinade on top of the fish and glaze in the oven for about 3-4 minutes.
Red cabbage mash:
Place purple cabbage with small amount of water in a blender; blend to make a thick but fine puree. Boil potatoes with garlic, ginger and green chilli in salt water till tender, drain well. Mash the potatoes thoroughly.
Heat butter and cream in a pan. Add the mashed potatoes, red cabbage puree and season with salt. Cook to a smooth mash consistency. Cool and fill in a piping bag.
Black crisp:
Mix all the ingredients in a bowl. Heat a non-stick pan over low heat. Pour about a tablespoon of the mixture into the pan and spread to form a circular disc of about 5cm diameter. Cook for 2-3 minutes or till crispy. Remove from pan and place on a kitchen towel.
Garnish:
Pipe the red cabbage mash on a plate, in concentric swirls. Place the fish, slightly off centre and rest the black crisp on it. Garnish with purple shisho and fennel flower.