What we hear when the cake mixture is about right (5)
I believe the answer is:
creak
'what we hear when' is the definition.
I can't judge whether this defines the answer.
'cake mixture is about right' is the wordplay.
'mixture' indicates an anagram.
'is about' means one lot of letters goes inside another.
'right' becomes 'r' (common abbreviation).
'cake' anagrammed gives 'ceak'.
'ceak' enclosing 'r' is 'CREAK'.
'the' is the link.
Can you help me to learn more?
(Other definitions for creak that I've seen before include "Groan (like a loose floorboard)" , "Audibly reveal weakness under strain" , "Harsh squeak like unoiled hinge" , "Squeaking sound" , "Screech, grate" .)