Preheat an oven to 175° C. Grease a 24x30cm baking dish. Whisk the rice flour, sugar, and baking powder together in a mixing bowl.
Beat the eggs, coconut extract, and vanilla extract in a mixing bowl until the eggs are smooth. Whisk in the milk, coconut milk, and melted butter until incorporated. Stir in the flour mixture a little at a time until no lumps remain; scrape into the prepared baking dish, and smooth the top.
Bake in the preheated oven until the mochi is golden brown, about 1 hour. Cool to room temperature before cutting into 24 pieces to serve.
Amount Per Serving Calories: 256 | Total Fat: 9g | Cholesterol: 56mg