Two kinds of party drink (5,3)
I believe the answer is:
green tea
'drink' is the definition.
(type of tea)
'two kinds of party' is the wordplay.
'two kinds of' becomes 'green' (I can't explain this - if you can you should give a lot more credence to this answer).
'party' becomes 'tea party' (tea party is a kind of party).
'green'+'tea'='GREEN TEA'
Can you help me to learn more?
(Other definitions for green tea that I've seen before include "Colourful drink for teenager" , "Brewed" , "Hot drink - teenager (anag)" , "Teen rage (anag.)" , "Infused drink" .)