Dreamy prediction of creamy onion soup (11)

I believe the answer is:

oneiromancy

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'dreamy prediction' is the definition.
The definition suggests a singular noun which matches the answer.

'creamy onion soup' is the wordplay.
'soup' is an anagram indicator.
'creamy'+'onion'='creamyonion'
'creamyonion' anagrammed gives 'ONEIROMANCY'.

'of' is the link.

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I've seen this clue in The Guardian.

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