Postcard Teas occupies a small shop on Duke Street, Mayfair, and operates on a principle that most cafés would not have the confidence to hold to: it sells only teas that the owner has sourced directly from small farmers, and it sells them properly. The interior is the size of a generous wardrobe. The service is unhurried and informative without being pedantic. Every tea on the menu comes with a postcard explaining who grew it and where. This is either exactly your thing or it isn't, and the shop is perfectly comfortable with either outcome.
Mayfair, London, United Kingdom