Delightful lake in rustic surroundings (8)
I believe the answer is:
pleasant
'delightful' is the definition.
(I've seen this before)
'lake in rustic surroundings' is the wordplay.
'lake in' becomes 'l' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'rustic' becomes 'peasant' (peasant is a kind of rustic).
'surroundings' is an insertion indicator.
'l' inserted into 'peasant' is 'PLEASANT'.
Can you help me to learn more?
(Other definitions for pleasant that I've seen before include "A greeable, affable" , "Refreshing" , "Satisfying, likeable" , "sweet?" , "Delightful" .)