Small portion, no starter, more than enough (5)
I believe the answer is:
ample
'enough' is the definition.
(ample means enough or plenty)
'small portion no starter more' is the wordplay.
I cannot really understand how this works, but
'starter' could be 'l' (as in a learner driver with L-plates on their car) and 'l' is found in the answer.
'more' could be 'm' and 'm' is found within the answer.
The remaining letters 'ape' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'than' acts as a link.
Can you help me to learn more?
(Other definitions for ample that I've seen before include "Easily sufficient" , "Large, accommodating" , "Buxom" , "Large enough" , "Large, capacious" .)