Preheat oven to 350 degrees.
Blend softened butter and sugar
Add evaporated milk, and water.
Add Mochiko flour, baking powder and blend until smooth
Add coconut milk and vanilla and combine well.
Pour into 9 X 13 pan. (no need to grease.)
Bake for one hour.
Let sit for 5-10 minutes. Enjoy warm, or let cool, seal and refrigerate.