I'm surprised chatty fan collapsed (5,4)

I believe the answer is:

fancy that

'i'm surprised' is the definition.
(expression of surprise)

'chatty fan collapsed' is the wordplay.
'collapsed' indicates an anagram.
'chatty'+'fan'='chattyfan'
'chattyfan' with letters rearranged gives 'FANCY THAT'.

(Other definitions for fancy that that I've seen before include "goodness" , "Well I'm blowed!" , "Imagine!" , "Gosh" , "exclamation of surprise" .)

I've seen this clue in The Guardian.

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