Quantity of coffee is steamed badly (9)

I believe the answer is:

demitasse

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'quantity of coffee' is the definition.
'demitasse' can be an answer for 'coffee' (demitasse is a kind of coffee). I'm not certain of the 'quantity of' bit.

'is steamed badly' is the wordplay.
'badly' indicates an anagram (letters in the wrong order).
'is'+'steamed'='issteamed'
'issteamed' anagrammed gives 'DEMITASSE'.

Can you help me to learn more?

(Other definitions for demitasse that I've seen before include "little cup" , "Coffee-cup" , "Small cup for black coffee" .)

I've seen this clue in The Telegraph.

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