Moisten meat in bottom (about time!) (5)
I believe the answer is:
baste
'moisten meat' is the definition.
(I've seen this in another clue)
'bottom about time' is the wordplay.
'bottom' becomes 'base' (base is a kind of bottom).
'about' indicates putting letters inside.
'time' becomes 't' (abbreviation).
'base' placed around 't' is 'BASTE'.
'in' acts as a link.
(Other definitions for baste that I've seen before include "strike" , "Looking at with interest" , "Sew" , "Pour hot fat over (meat)" , "Beast (anag.)" .)