Stevens back with large Mexican snacks (5)
I believe the answer is:
tacos
'mexican snacks' is the definition.
(I've seen this in another clue)
'stevens back with large' is the wordplay.
'stevens' becomes 'cat' (I can't justify this - if you can you should give a lot more credence to this answer).
'back' says the letters should be written in reverse.
'with' says to put letters next to each other.
'large' becomes 'os' (abbreviation for oversize).
'cat' back-to-front is 'tac'.
'tac'+'os'='TACOS'
Can you help me to learn more?
(Other definitions for tacos that I've seen before include "Mexican food" , "pancakes" , "Mexican wraps" , "Mexican dish" , "Foreign dish" .)