Fish stew consumed in grotty motel (8)

'fish stew' is the definition.
(matelote is a kind of fish stew)

'consumed in grotty motel' is the wordplay.
'consumed' becomes 'ate' (eating is a kind of consuming).
'in' indicates putting letters inside.
'grotty' indicates anagramming the letters (I've seen this in other clues).
'motel' anagrammed gives 'mlote'.
'ate' put into 'mlote' is 'MATELOTE'.