The most common and most likely answer to this crossword clue is the 6 plus 3 letter word SCOTCH EGG
I've seen this crossword clue in Independent
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More clues leading to the result SCOTCH EGG
- After drink get urge for a nibble
- Butterless sweet, say, grand teatime fare?
- Food and drink for one waiting at last
- Put a stop to, say, front of grocery offering snack?
- Snack in foil, say pig’s foot
- Quash urge for snack
- Eliminate urge for deep-fried food
- She consumes French Malbec cold, doubly good with a snack
- East Germans ruin first snack
- Suppress urge for food
Buddy explains!

The straight part
We know that "a snack" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a snack = scotch egg.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.