Absolutely no more cake! (4-3)

I believe the answer is:

dead-set

'absolutely' is the definition.
(I've seen this before)

'no more cake' is the wordplay.
'no more' becomes 'dead' (if someone is no more they are dead).
'cake' becomes 'set' (cake can mean to set or harden).
'dead'+'set'='DEAD-SET'

I've seen this clue in The Independent.

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