For butter, blend every one of the ingredients collectively in a sizable bowl, then beat really with a wooden spoon until there aren't any lumps of butter left. Spoon onto a large sheet of cling film, after that put firmly in a sausage shape. Chill until firm (or added the freezer if you are short of time).
Put up a pan with a steamer or suspend a heatproof colander outrageous of a pan. Cut the leeks by 50 percent lengthways, then slice into long pieces, towards depth of tagliatelle. Cover, after that vapor for 6 minutes until tender, without signs and symptoms of squeakiness. Season, after that set aside.
Dry the scallops on kitchen paper and season. Heat a heavy-based pan, adding the oil. Once hot, include the scallops, maintaining all of them near together – this helps the sides to remain straight and tall rather than sagging. Sizzle for just two mins until caramelised and you can begin to see the temperature creeping up the exterior. Start with a palette blade, then fry for 1 min much more. Remove the heat, you can add several good cuts regarding the butter towards the cooking pan, spooning across scallops because it melts.
To provide, wind a nest of hot leeks in the centre of 4 dishes, top every with 3 scallops, spoon on the buttery sauce (it looks wise trickled round the dish), after that sprinkle utilizing the continuing to be parsley. Squeeze over only a little lemon liquid just before tuck-in.