Youth's spell as a vegetarian? (5,4)
I believe the answer is:
salad days
'youth's' is the definition.
(I've seen this before)
'spell as a vegetarian?' is the wordplay.
I cannot really understand how this works, but
'as' could be 'ala' (French 'a la' - 'in the style of') and 'ala' is present in the answer.
'a' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for salad days that I've seen before include "Period of youth and inexperience - ate lettuce dishes?" , "musical" , "when one is young?" , "Best time of youth" , "Youth; heyday" .)