Dropped portion of ratatouille? Footman recoiled! (4)
I believe the answer is:
fell
'dropped' is the definition.
(I've seen this before)
'portion of ratatouille? footman recoiled' is the wordplay.
'portion of' indicates the answer is hidden within the clue.
'recoiled' is a reversal indicator (I've seen 'recoil' mean this).
'llef' is hidden within 'ratatouille footman'.
'llef' back-to-front is 'FELL'.
(Other definitions for fell that I've seen before include "avalanche?" , "Brutal -- high moorland" , "Toppled" , "stretch of moorland" , "animal skin" .)