Pleasant entertaining hour in recess (5)
I believe the answer is:
niche
'recess' is the definition.
('niche' can be a synonym of 'recess')
'pleasant entertaining hour' is the wordplay.
'pleasant' becomes 'nice' ('nice' is associated in meaning with 'pleasant').
'entertaining' is an insertion indicator.
'hour' becomes 'h'.
'nice' placed around 'h' is 'NICHE'.
'in' acts as a link.
(Other definitions for niche that I've seen before include "Small corner of e.g. market" , "small specialised market" , "Suitable position (in market, life etc)" , "somewhere comfortable" , "Suitable spot" .)