Begin by washing the glutinous rice under cold water to remove any impurities and rice dust.
Soak the rice overnight in 1.5 cups of water. This step ensures that the rice is sufficiently hydrated, making grinding easier.
After soaking, drain the rice and add it to the blender with ¼ to ½ cup of fresh water or as needed. Blend until you get a smooth paste.
Line a fine mesh strainer with a fine linen cloth and place on top of a large bowl.
Pour the blended rice mixture through it. Gather the edges of the cloth and lightly cover the top of the rice mixture with it.
Let the mixture sit in the strainer for 30 minutes to an hour. The water will naturally drain into the bowl.
Then, place a heavy object, like a bowl or small pan, on top to apply pressure and help release the rest of the water. Leave it for a minimum of 8 hours to overnight.
Once the water is completely drained, open the cloth to find the hydrated rice flour.
Break it into small pieces to help it dry more easily. Spread these on a baking sheet if you’re sun-drying, or prepare for oven/dehydrator use.
For sun drying, ensure it’s a hot, sunny day. For oven drying, set to the lowest setting, ideally around 150°F (65°C), and check periodically until it is completely dry.
Break or rub the dried flour to crush any lumps, then sift through a fine mesh sieve to collect the fine powder.
For best freshness, store the flour in an airtight container at room temperature for up to a month or in the freezer for up to three months.