Toffee, small, found in street (5)
I believe the answer is:
sweet
'toffee' is the definition.
The definition and answer can be both things that one consumes for nourishment as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'small found in street' is the wordplay.
'small' becomes 'wee' (Scottish term for small).
'found in' means one lot of letters goes inside another.
'street' becomes 'st' (abbreviation).
'wee' inserted inside 'st' is 'SWEET'.
Can you help me to learn more?
(Other definitions for sweet that I've seen before include "Dulcet - dessert" , "Sugary - but might be tart!" , "darling" , "Having a sugary taste" , "Amiable" .)