Grouse cooked for scoundrels (6)
I believe the answer is:
rogues
'for scoundrels' is the definition.
(rogue is a kind of scoundrel)
'grouse cooked' is the wordplay.
'cooked' indicates an anagram (letters cooked into a new form).
'grouse' with letters rearranged gives 'ROGUES'.
(Other definitions for rogues that I've seen before include "Varlets" , "Wild animals driven away from the herd" , "Rascals" , "Scoundrels, miscreants" , "'Scoundrels, charlatans (6)'" .)