Booked dish out to be eaten by Ginger (8)
I believe the answer is:
reserved
'booked' is the definition.
('reserve' can be a synonym of 'book')
'dish out to be eaten by ginger' is the wordplay.
'dish out' becomes 'serve' (as in dishing out food).
'to be eaten by' is an insertion indicator.
'ginger' becomes 'red ginger' (red ginger is a kind of ginger).
'serve' placed within 'red' is 'RESERVED'.
(Other definitions for reserved that I've seen before include "Uncommunicative, not extrovert" , "Bashful" , "Slow to reveal opinions; kept by" , "Kept back" , "cool" .)