Combine 3 1/3 cups rice flour, 2/3 cup tapioca starch, and 1 1/4 cups fermented rice water. Knead well for about 15–20 minutes. Let the dough rest and rise for 4–5 hours until bubbly. Kneading is essential for the cake to develop its honeycomb texture.

Prepare a steamer with boiling water. Pour the batter into the molds and steam. The cake is done when a toothpick inserted comes out clean. Alternative method: Place a tray of boiling water in the oven, set to 340°F (170°C), and bake the cakes in a water bath.

Both methods yield delicious cakes. Steaming makes the cake softer, while baking gives the surface a slight crust, but the quality is just as good and it's more convenient.

Serve with coconut sauce and toasted sesame seeds. For the coconut sauce: Mix 3/4 cup coconut milk, 1/3 cup cornstarch, and a pinch of salt.