Coconuts rarely thrive in Kibungan maybe because of its climate and mountainous land formations.
Because I have heard from elders in Kibungan that they used to travel down to La Union or Ilocos Region to barter or buy salt, sugar and sea foods, it could be concluded that they were also introduced with coconut shells as bowls.
In most of the grand cañaos or otherwise spelled as "kanyaw" I have attended when I was a kid, I have noticed the use of coconut shells as bowls. It was commonly used for soups (sabaw) especially meat.
Aside from soups, "Silap" was used to crush chilli (sili) with salt through the use of a piece of wood, which was especially prepared for that purpose (like mortar and pestle).
The earliest bowls were actually wooden bowls. The trunks of matured trees were manually chiseled to form bowls. Not all trees could be made into bowls since some tree trunks could easily break when constantly poured with hot soups.
When I was a kid, however, very few families in Kibungan who were able to secure those indigenous kitchen utensils. (I hope that there are families who are still keeping indigenous wooden bowls today.)
Meanwhile, it is nostalgic to me upon seeing the "Silap" being used during lunch time of the first Kankanaey Festival at the Kibungan Municipal Hall today (May 13, 2023).