Tantrums over fish being too hot (8)
I believe the answer is:
'too hot' is the definition.
I can't tell whether this defines the answer.
'tantrums over fish' is the wordplay.
'tantrums' becomes 'fits' ('fit' can be a synonym of 'tantrum').
'over' is a reversal indicator.
'fish' becomes 'ling' (ling is a kind of fish).
'fits' back-to-front is 'stif'.
'being' is the link.
Can you help me to learn more?
(Other definitions for stifling that I've seen before include "really hot", "Unpleasantly hot or airless", "Flings it in suffocating manner", "Smothering or suppressing", "Oppressively hot and airless".)