The best solver gets a biscuit (5,7)
I believe the answer is:
'a biscuit' is the definition.
(I've seen this before)
'the best solver' is the wordplay.
'the best' becomes 'cream' (as in 'the cream of the crop').
'solver' becomes 'cracker' (someone who cracks things).
'gets' acts as a link.
(Another definition for cream cracker that I've seen is " Biscuit".)