Shopper in Cardiff perhaps eating fresh brie for snack (5,7)
I believe the answer is:
welsh rarebit
'snack' is the definition.
(I have seen 'Toasted snack ' mean 'welsh rarebit' so perhaps 'snack' could also mean 'welsh rarebit')
'shopper in cardiff perhaps eating fresh brie' is the wordplay.
I cannot quite understand how this works, but
'perhaps' could be 'rare' (a steak can be served rare) and 'rare' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'for' acts as a link.
Can you help me to learn more?
(Other definitions for welsh rarebit that I've seen before include "Cheese on toast" , "cheesy meal" , "Toasted snack" , "Cheesy dish" .)