... delivered - 100% beef goodness! (4,3)

I believe the answer is:

holy cow

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

'goodness' is the definition.
(I have seen 'The goodness' mean 'holy cow' so perhaps 'goodness' could also mean 'holy cow')

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for holy cow that I've seen before include "Blimey!" , "The goodness" .)

I've seen this clue in The Independent.

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