Pie top all crumbly in papery frill (9)

I believe the answer is:

papillote

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'papery frill' is the definition.
The definition suggests a singular noun which matches the answer.

'pie top all crumbly' is the wordplay.
'crumbly' is an anagram indicator.
'pie'+'top'+'all'='pietopall'
'pietopall' with letters rearranged gives 'PAPILLOTE'.

'in' acts as a link.

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I've seen this clue in The Independent.

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