Make up lobster stock using the following ingredient: mirepoix of veg, lobster shell, tomato purée, white wine, brandy and fish stock. Simmer for 25mins.
Pass the stock through a fine sieve, reduce and finish with chopped fresh vegetables and a little double cream. Season with salt and pepper.
Cut the salmon and cod into 2-3cm chunks. Poach them in a little fish stock and white wine until cooked. Add the mussels to the stock.
Pan fry the seabass fillet whole until cooked through, ensuring the skin is nice and crispy. Slice into 1cm strips.
Assemble in a large bowl, pouring the sauce around the fish and decorating with mussels and fresh dill.