Started with dessert (4)
I believe the answer is:
tart
'dessert' is the definition.
(type of dessert)
'started with' is the wordplay.
'with' indicates a hidden word.
'TART' can be found hidden inside 'started'.
(Other definitions for tart that I've seen before include "Acidulous" , "Somewhat sour like flat cake" , "The pastry sounds bitter" , "Open cake with jam etc" , "Sharp on the tongue" .)