I see them in summer being sold off huge flat trays on the back of bicycles leaned on stands under shady trees. They are often displayed with avocados. They look like avocados. Big avocados with prickly bumps on them.
These ones were being whizzed up in a blender at the Hoi An market, with sugar, condensed milk, a bit of water and lots of crushed ice. In Vietnam, avocados are considered fruit and eaten or drunk as such.
But what are these big avocados with prickly bumps on them? I've been googling for a good half hour. I even googled "big avocados with prickly bumps on them."