Face fine for concocting stimulant (8)

I believe the answer is:

caffeine

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

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

'face fine for concocting' is the wordplay.
'face fine' can be anagrammed to 'CAFFEINE'.
Though, I am not clear how this is indicated.

Can you help me to learn more?

(Other definitions for caffeine that I've seen before include "Stimulating substance in coffee" , "Stimulant in, eg, cappuccino" , "Compound in coffee" , "Stimulant found in many beverages" , "Stimulating alkaloid" .)

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

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