On an atoll the sweet is what you can make from a coconut. Karewe toddy boiled into kamaimai is the syrup. People pour it on fruit or bread. Dried fish is the other handful. There is no Kiribati KitKat origin story to invent.
Shops sell biscuits when the boat has come. Pack syrup if it is bottled, and copra products. Fresh toddy is a same-day drink. Honesty is the atlas job here: coconut syrup and ship biscuits, not a fake pastry heritage.