Drunkard went over to thank father for Mexican food (7)
I believe the answer is:
tostada
'mexican food' is the definition.
(I've seen this before)
'drunkard went over to thank father' is the wordplay.
'drunkard' becomes 'sot' (sot can mean a drunken person).
'went over' shows that the letters should be reversed in order (I've seen 'gone over' mean this).
'to thank father' becomes 'tada' (I can't explain this - if you can you should give a lot more credence to this answer).
'sot' in reverse letter order is 'tos'.
'tos'+'tada'='TOSTADA'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for tostada that I've seen before include "Mexican food" , "Mexican topped pancake" , "Crisp 15 down" , "spicy food" .)