What might accompany crackers list lad keeps? (7)
I believe the answer is:
stilton
'what might accompany crackers' is the definition.
(crackers might be eaten with stilton cheese)
'list lad keeps?' is the wordplay.
'list' becomes 'tilt' (both can mean to lean).
'lad' becomes 'son' (lad can informally mean a young boy).
'keeps?' means one lot of letters goes inside another (inserted letters are kept inside).
'tilt' inserted inside 'son' is 'STILTON'.
(Other definitions for stilton that I've seen before include "Strong Eng. cheese" , "Lost tin (anag)" , "Cheese variety" , "Strong English cheese, originally from Leicestershire" , "Strong blue cheese" .)