Work schedule in bistro, taxing (4)
I believe the answer is:
rota
'work schedule' is the definition.
(I've seen this before)
'in bistro taxing' is the wordplay.
'in' says the answer is hidden in the clue.
'ROTA' is hidden within 'bistro taxing'.
(Other definitions for rota that I've seen before include "Cycle of duty" , "List assigning turns of duty" , "Register of names for duties" , "Duty roster" , "List of duties to be done, or people to do them" .)