Hot in pleasant recess (5)
I believe the answer is:
niche
'recess' is the definition.
('niche' can be a synonym of 'recess')
'hot in pleasant' is the wordplay.
'hot' becomes 'h'.
'in' indicates putting letters inside.
'pleasant' becomes 'nice' ('nice' is associated in meaning with 'pleasant').
'h' put within 'nice' is 'NICHE'.
(Other definitions for niche that I've seen before include "Specialist area" , "Suitable slot" , "ideal position" , "Recess; place in life" , "somewhere comfortable" .)