Bodevici specialises in Tigernut milk, also known as Horchata (orxata in Catalan). They even sell it by the bottle. While this is quite a common drink in Spain, I particularly like this place because they have a sugarfree option. Barcelona has tons of vegan options when it comes to ice cream but this is the only place I know of that serves tigernut milk ice cream. It has a really interesting flavour: nutty and earthy, and pairs very well with their agave-sweetened chocolate ice cream.
Tigernut milk ice cream