What’s He Selling?

There are many mysteries in the Kingdom of Wonder.  One of them for me is what kind of street food this guy is selling.  You see all sorts of things sold on the street, many of them foods that would not be street food in the U.S., like corn on the cob, but I’m not sure what this man is vending.  I can tell there is some shredded lettuce or similar vegetable and some other yellowish vegetable, but is that the main ingredient or just a garnish for something else?  And what is the mortar and pestle for?  He’s ladling some juice into the mortar but the end product is an unknown for me.