Butter mochi is a Hawaiian dessert of mochi enriched with sugar, butter, and either coconut milk or milk. It is similar to Japanese mochi but much richer and sweeter. It is a common homemade treat across the Hawaiian islands.
The source of butter mochi is not entirely known but multiple observers have noted the similarity to the Filipino dessert, bibingka, which itself was probably invented in the Portuguese settlement of Goa prior to the 19th century. It is possible that butter mochi is a modern Hawaiian interpretation of an idea brought to the islands by Portuguese immigration, which is the source of numerous other Hawaiian dishes and ingredients. Alternatively, it may have been invented on the islands as a fusion of the Japanese mochi tradition with European dairying practices. Laudan (1996) opines that the most likely scenario is that both origins are true and that the dish emerged as part of the Hawaiian "local food" fusion.