The obvious place to eat Cruceño food rather than international food: majadito, locro, sonso, keperí, and whatever the day's soup is, served in a colonial house built around a courtyard with the old water cistern the restaurant is named after.
It is a sit-down lunch rather than a quick one, and lunch is when eastern Bolivian cooking is at its best — the main meal of the day here, and the kitchen treats it that way.