Trendy drink I had is bland (7)
I believe the answer is:
insipid
'is bland' is the definition.
(synonyms)
'trendy drink i had' is the wordplay.
'trendy' becomes 'in' ('in' can mean fashionable).
'drink' becomes 'sip' (sipping is a kind of drinking).
'i had' becomes 'i'd' (I'd).
'in'+'sip'+'id'='INSIPID'
(Other definitions for insipid that I've seen before include "Lacking in flavour or interest" , "Bland, flavourless" , "without taste" , "Jejune" , "Wishy-washy" .)