Lightly cooked delicacy - that's special (4,5)

I believe the answer is:

rare treat

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'special' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'lightly cooked delicacy' is the wordplay.
'lightly cooked' becomes 'rare' (as in a rare steak).
'delicacy' becomes 'treat' (synonyms).
'rare'+'treat'='RARE TREAT'

'that's' acts as a link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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