Baguette ingredient caused fever (4)
I believe the answer is:
ague
'fever' is the definition.
(I've seen this in another clue)
'baguette ingredient caused' is the wordplay.
'AGUE' is hidden within the letters.
But, I'm uncertain how this is indicated.
Can you help me to learn more?
(Other definitions for ague that I've seen before include "Illness with fever and shivering, malaria say" , "nasty illness?" , "Sweating, shivering, fit (once)" , "Sickness" , "Malarial fever or fit of shivering" .)