Article in large house, something that adds taste (7)
I believe the answer is:
vanilla
'something that adds taste' is the definition.
(vanilla is a flavouring)
'article in large house' is the wordplay.
'article' becomes 'an' (indefinite article).
'in' is an insertion indicator.
'large house' becomes 'villa' (I've seen this before).
'an' put inside 'villa' is 'VANILLA'.
(Other definitions for vanilla that I've seen before include "Pod used in cookery" , "Tasty flavouring for ice-cream" , "Basic ice-cream" , "Flavouring from orchid pods" , "devoid of special features" .)