Filling food set out -- stray dog gets stuck in (6)
I believe the answer is:
stodge
'filling food' is the definition.
(I've seen this in another clue)
'set out stray dog gets stuck in' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'stray' indicates anagramming the letters.
'gets stuck in' indicates putting letters inside.
'dog' with letters rearranged gives 'odg'.
'set' with letters rearranged gives 'ste'.
'ste' enclosing 'odg' is 'STODGE'.
(Other definitions for stodge that I've seen before include "Heavy pud" , "heavy fare" , "Heavy and indigestible food" , "Heavy, often starchy, food" , "Heavy filling food" .)