Eggs are too set in the middle always (3)
I believe the answer is:
roe
'eggs' is the definition.
(fish eggs)
'too set in the middle always' is the wordplay.
'too set' becomes 'ro' (I can't explain this - if you can you should believe this answer much more).
'in the middle' says to take the centre.
'always' becomes 'eer' (poetic way of saying ever).
The central letter of 'eer' is 'e'.
'ro'+'e'='ROE'
'are' acts as a link.
Can you help me to learn more?
(Other definitions for roe that I've seen before include "shy animal" , "Swift runner" , "If hard, eggs" , "eg Caviare" , "Food from fish" .)