Miss tea when involved in painting (7)
I believe the answer is:
matisse
'painting' is the definition.
(a painting by Henri Matisse)
'miss tea when involved' is the wordplay.
'when involved' indicates an anagram (involved can mean confusing or complex).
'miss'+'tea'='misstea'
'misstea' with letters rearranged gives 'MATISSE'.
'in' acts as a link.
(Other definitions for matisse that I've seen before include "French painter, d. 1954" , "20th century French painter" , "Is mates turned on the French painter" , "Henri -, nineteenth-twentieth century French painter/sculptor" , "Henri ---, Twentieth Century painter" .)