Shadowed with a stem (7)
I believe the answer is:
stalked
'shadowed' is the definition.
(stalking is a kind of shadowing)
'stem' is the wordplay.
I cannot quite understand how this works, but
'stem' could be 'stalk' (synonyms) and 'stalk' is found within the answer.
The remaining letters 'ed' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'with a' acts as a link.
Can you help me to learn more?
(Other definitions for stalked that I've seen before include "Tracked stealthily, game or victim" , "Pursued (someone) to an obsessive degree" .)