The most common and most likely answer to this crossword clue is the 5 plus 7 letter word WELSH RAREBIT
I've seen this crossword clue in The Guardian
W
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More clues leading to the result WELSH RAREBIT
- What could make one rebel — this raw item of food
- Herb stew liar perhaps made out to be cheese dish
- Run away without paying for excellent piece of cheesy snack
- British shopper obtains fresh Brie to make cheesy meal
- Erstwhile bar served up snack
- Dish erstwhile bar concocted
- Wife has terrible stew dish
- Cheese dish arbiter shrewdly prepared is not dry
- Dish with herbs Walter ordered touring Italy
Buddy explains!
The straight part
We know that "cheesy snack" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cheesy snack = welsh rarebit.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.