Wrong end of apple cake (5)
I believe the answer is:
torte
'cake' is the definition.
(torte is a kind of cake)
'wrong end of apple' is the wordplay.
'wrong' becomes 'tort' (legal term).
'end of' indicates one should take the final letters.
The final letter of 'apple' is 'e'.
'tort'+'e'='TORTE'
(Other definitions for torte that I've seen before include "Rich (Austrian) cake or pastry" , "Sweet cake or tart" , "Rich food" , "Rich sweet cake" , "1d [PASTRY]" .)