Very hot spot in the middle of jungles (6)
I believe the answer is:
piping
'very hot' is the definition.
(I've seen this before)
'spot in the middle of jungles' is the wordplay.
'spot' becomes 'pip' (both can mean a small amount).
'the middle of' indicates the central letters.
The middle letter of 'jungles' is 'g'.
'pip'+'in'+'g'='PIPING'
(Other definitions for piping that I've seen before include "Lengths of tube" , "Tube; very hot" , "really hot" , "Metal or plastic tubing, or trimming on garment" , "Long tubes" .)