For VAT purposes, there is an important distinction between:
(1)supplies of hot food (e.g. fish and chips) and supplies of cold food (e.g. sandwiches); and
(2)supplies of food for consumption on the premises on which the food is supplied (e.g. in a restaurant, café or bar; being standard-rated catering (¶20-300)) and supplies of food for consumption elsewhere (e.g. in an office, in a park or at home).
Thus, food which is zero-rated when sold by a supermarket becomes standard-rated when made into a meal by a restaurateur.