Surprisingly, most of army deem granola a breakfast favourite (6,9)

I believe the answer is:

orange marmalade

I'm a little stuck... Click here to teach me more about this clue!

'breakfast favourite' is the definition.
The definition and answer can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps you can see an association between them that I don't see?

'surprisingly most of army deem granola a' is the wordplay.
'surprisingly' indicates an anagram.
'most of' means to remove the last letter.
'army' with its last letter taken away is 'arm'.
'arm'+'deem'+'granola'+'a'='armdeemgranolaa'
'armdeemgranolaa' anagrammed gives 'ORANGE MARMALADE'.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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