Essentially claim mushrooms given to middlemen over there were exceptional (8)
I believe the answer is:
especial
'exceptional' is the definition.
(I know that exceptional can be written as especial)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for especial that I've seen before include "Exclusive" , "Over and above what is usually expected" , "Exceptional" , "Unusual" , "Spice ale wrongly and be particular" .)