Teen chose wrong oven dish (6,2,5)
I believe the answer is:
cheese on toast
'dish' is the definition.
(type of dish)
'teen chose wrong oven' is the wordplay.
'wrong' is an anagram indicator.
'oven' becomes 'oast' (type of kiln).
'teen'+'chose'='teenchose'
'teenchose' with letters rearranged gives 'cheeseont'.
'cheeseont'+'oast'='CHEESE ON TOAST'
(Other definitions for cheese on toast that I've seen before include "Welsh rabbit" , "quick snack?" .)