To make the sauce....put the Pink grapefruit juice, dry sherry, garlic, and
ginger into a sauce pan and reduce by ¾. Then add the fish stock and reduce by half
before finally adding the cream and again reducing by half. Whisk in the butter, a little
at a time until it is all incorporated and then add the green part from the spring onions.
Dip the Tuna steaks in the oil and season with the salt, cracked black pepper and chilli flakes
and cook on a pre – heated griddle pan for two or three minutes per side (this is dependant on whether
you like your Tuna medium rare or medium).
To serve.......reheat the spaghetti in the microwave for two minutes (ensuring that it
is hot)! Divide between four pasta bowls and top each mound of spaghetti with a Tuna steak.
Garnish with the pink grapefruit segments and the spring onions.
Notes......When whisking the butter into the sauce, it must be done over a low
heat so that the sauce does not boil, otherwise, it will split.