Mother unfortunately overturned spice mix (6)
I believe the answer is:
masala
'spice mix' is the definition.
(I've seen this before)
'mother unfortunately overturned' is the wordplay.
'mother' becomes 'ma' (ma is a kind of mother).
'unfortunately' becomes 'alas' (I've seen this before).
'overturned' shows that the letters should be reversed in order.
'alas' reversed gives 'sala'.
'ma'+'sala'='MASALA'
(Other definitions for masala that I've seen before include "Indian curry" , "Spice mix" , "A mixture of Indian spices" , "Spice blend" , "hot dish?" .)