Egg on top of toast abandoned unfinished (5)
I believe the answer is:
tempt
'egg' is the definition.
Although both the answer and definition are verbs in their base form, I cannot see how they can define each other.
'on top of toast abandoned unfinished' is the wordplay.
'on top of' says to put letters next to each other.
'toast' becomes 'prosit' (I've seen this in another clue).
'abandoned' suggests removing the centre (middle letters abandon or vacate the word).
'unfinished' becomes 'tem' (I can't explain this - if you can you should give a lot more credence to this answer).
'prosit' with its centre taken out is 'pt'.
'pt' put after 'tem' is 'TEMPT'.
Can you help me to learn more?
(Other definitions for tempt that I've seen before include "Entice - persuade" , "Entice (to sin)" , "Entice, lure" , "Coax" , "Entice - dare" .)