Not your usual breakfast item - startled grocer reduced this - good (7,3)

I believe the answer is:

ostrich egg

'not your usual breakfast item' is the definition.
(rather than a hen's egg)

'startled grocer reduced this good' is the wordplay.
'startled' indicates an anagram.
'reduced' means to remove the last letter.
'good' becomes 'g' (abbreviation).
'grocer' with its final letter taken away is 'groce'.
'groce'+'this'='grocethis'
'grocethis' is an anagram of 'ostricheg'.
'ostricheg'+'g'='OSTRICH-EGG'

I've seen this clue in The Independent.

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