The liqueur, plan to do something with again (10)
I believe the answer is:
chartreuse
'the liqueur' is the definition.
(Chartreuse is an example)
'do something with again' is the wordplay.
'do' becomes 'char' (I've seen this before).
'something' becomes 'tuse' (I can't justify this - if you can you should give a lot more credence to this answer).
'with' indicates putting letters inside.
'again' becomes 're' (prefix meaning 'again').
'tuse' placed around 're' is 'treuse'.
'char'+'treuse'='CHARTREUSE'
'plan to' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for chartreuse that I've seen before include "green liquid" , "The spirit" , "Green-yellow liqueur" , "Carthusian liqueur" , "drink" .)