Undercooked morsel that's eaten (7)

I believe the answer is:

rarebit

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'that's eaten' is the definition.
I can't tell whether this definition defines the answer.

'undercooked morsel' is the wordplay.
'undercooked' becomes 'rare' (I've seen this in another clue).
'morsel' becomes 'bit' (synonyms).
'rare'+'bit'='RAREBIT'

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(Other definitions for rarebit that I've seen before include "cheesy meal" , "Arbiter of tasty Welsh dish of cheese on toast" , "Savoury dish of cheese on toast" , "on Welsh table?" , "Simple dish" .)

I've seen this clue in The Globe and Mail.

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