Throw cakes without topping down (6)
I believe the answer is:
unseat
'throw' is the definition.
(to unseat is to throw out or oust)
'cakes without topping down' is the wordplay.
'cakes' becomes 'buns' (cake is a type of bun).
'without topping' means to remove the first letter (the top letter is removed).
'down' becomes 'eat' (I've seen this in other clues).
'buns' with its initial letter taken off is 'uns'.
'uns'+'eat'='UNSEAT'
(Other definitions for unseat that I've seen before include "Dislodge from saddle" , "Throw (as a 15?)" , "Remove from power" , "Get out of office" , "Remove from horse (or house?)" .)