Line a baking sheet with parchment paper and set it aside.

Make the starter: In a small, microwave-safe bowl combine ¼ cup (1¼oz/35g) of the sweet rice flour with 3 tablespoons of milk and heat for about 30 seconds, until the mixture comes together like a sticky dough. (you can also cook this briefly over the stove.) Set aside to let cool.

In a medium bowl, combine the remaining 1 ¾ cup (8¾oz/247g) of Sweet Rice Flour, sugar, and baking powder.

In a separate small bowl, whisk together the remaining ½ cup (4floz/120ml) milk, egg, and butter, and then combine with the dry ingredients.

Add in the cooled starter and knead together until a smooth and soft dough is formed. If the dough feels a bit firm, add a touch more milk, one teaspoon at a time, until the dough is soft but still firm enough to hold its shape.

Divide the dough into 8 equally sized portions and keep a small bowl of water nearby.

Working with one portion of dough at a time, divide the dough into 8 small pieces, wet your hands, and roll each piece of dough into a small ball. Press the small balls of dough into a ring shape and place them on your prepared baking sheet while you shape the rest of your donuts.

Once shaped, pour oil 2-inches (5cm) deep into a heavy-bottomed pot and using a thermometer, heat to 350°F (180°C). Place a wire rack on a baking sheet next to the stove.

Once the oil is hot, fry the donuts, one at a time for about 2 minutes per side, until golden. Transfer with tongs or a slotted spoon to the wire rack to let drain while you fry the rest of the donuts.

Make the glaze: In a shallow bowl, whisk the powdered sugar, 2 tablespoons of milk, and the ube extract together until smooth. If you would like a thinner glaze, add the 3rd tablespoon of milk.

One at a time, dip each donut into the glaze and return to the wire rack to let set.

Enjoy! These donuts are best served just after they are made. Store leftovers in an airtight container at room temperature for up to 2 days.