Nutty Scottish leader once losing face (6)
I believe the answer is:
almond
'nutty' is the definition.
(almond can mean almond-flavoured)
'scottish leader once losing face' is the wordplay.
'scottish leader once' becomes 'Salmond' (Alex Salmond, former First Minister of Scotland).
'losing face' means to remove the first letter.
'salmond' with its initial letter taken off is 'ALMOND'.
(Other definitions for almond that I've seen before include "Nut (tree)" , "Fruit for marzipan" , "Nutlike seed" , "Type of nut" , "Old man (anag)" .)