Dad swamps kir cocktail with spice (7)
I believe the answer is:
paprika
'spice' is the definition.
(I know that paprika is a type of spice)
'dad swamps kir cocktail' is the wordplay.
'dad' becomes 'papa' (synonyms).
'swamps' indicates putting letters inside (inserted letters are covered up or swamped).
'cocktail' indicates an anagram.
'kir' anagrammed gives 'rik'.
'papa' going around 'rik' is 'PAPRIKA'.
'with' acts as a link.
(Other definitions for paprika that I've seen before include "Condiment" , "Sweet red pepper" , "Seasoning made from pepper" , "Irk papa with mild red pepper" , "strong-tasting spice" .)