Fiddle & Piano with one seafood option (6)

I believe the answer is:
scampi
'seafood option' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'fiddle piano with one' is the wordplay.
'fiddle' becomes 'scam' (I've seen this in other clues).
'piano' becomes 'p' (musical abbreviation).
'with' means one lot of letters go next to another.
'one' becomes 'i' (Roman numeral).
'scam'+'p'+'i'='SCAMPI'
Can you help me to learn more?
(Other definitions for scampi that I've seen before include "Breaded prawns" , "Large prawns cooked in batter" , "Dish of fried shrimp or prawns" , "Norway lobsters -- Dublin Bay prawns" , "Prawns (fried with breadcrumbs)" .)
