Crossword Genius

Punch accompanying jam and vanilla slice (4,5)

Ross

I believe the answer is:

snot block

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'punch accompanying' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'jam and vanilla slice' is the wordplay.
'jam' becomes 'block' (synonyms).
'and' says to put letters next to each other.
'vanilla slice' becomes 'snot' (I can't explain this - if you can you should give a lot more credence to this answer).
'block' put after 'snot' is 'SNOT BLOCK'.

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I've seen this clue in the Sydney Morning Herald.
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