Thrash with stick (5)
I believe the answer is:
paste
I believe this clue is a double definition.
'thrash' is the first definition.
(I know that thrash is a more specific form of the action beat)
'stick' is the second definition.
(I've seen this before)
'with' acts as a link.
(Other definitions for paste that I've seen before include "An adhesive, or material for artificial gems" , "Watery cement" , "Sticky stuff" , "Tapes (anag.)" , "Dough - adhesive - gem substitute" .)