Sausage ingredient that'll make you look tired (3)
I believe the answer is:
sag
'look tired' is the definition.
'sausage ingredient' is the wordplay.
'ingredient' indicates a hidden word (I've seen 'ingredient of' mean this).
'SAG' is hidden in the letters of 'sausage'.
'that'll make you' acts as a link.
(Other definitions for sag that I've seen before include "Droop in the middle - it's gas" , "Lose energy" , "Drop" , "Fail to retain interest" , "Droop, flag" .)