A very small amount in this sweet (1,6)
I believe the answer is:
a trifle
'this sweet' is the definition.
The definition and answer can be both related to thinking as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'a very small amount' is the wordplay.
I cannot really understand how this works, but
'a' is found in the answer.
'amount' could be 'trifle' (I have seen 'small amount' mean 'trifle' so perhaps 'amount' could also mean 'trifle') and 'trifle' is present in the answer.
No letters remain.
This explanation may well be incorrect...
'in' is the link.
Can you help me to learn more?
(Other definitions for a trifle that I've seen before include "somewhat" , "Slightly" .)