Step 1

Place 1/4 cup white sesame seeds in a small frying pan over medium heat and cook, stirring constantly, until fragrant and light golden brown, 2 to 5 minutes.

Step 2

Transfer to a mortar and pestle, let cool, and coarsely crush. (Alternatively, let cool in the frying pan, then transfer to a zip top bag and coarsely crush with a rolling pin.) Transfer to a small bowl. Add 1/4 cup granulated sugar and stir to combine.

Step 3

Place 2 cups mochiko sweet rice flour and 1 cup water in a large bowl and knead until a smooth and pliable dough is formed (the mixture may look dry at first, but keep kneading until it comes together), 1 to 2 minutes.

Step 4

For an optional ube variation: Divide the dough in half. Add 1/4 teaspoon ube extract to one half and knead with gloved hands until evenly colored.

Step 5

Line a baking sheet with parchment paper. With mochiko-floured hands, divide the dough into 12 pieces (about 2 generous tablespoons each), and roll each portion into a ball. Place on the baking sheet, spacing them evenly apart. Flatten each ball with your palm into a 2-inch wide disc.

Step 6

Bring a large pot of water to a boil over medium-high heat. Meanwhile, place 1 cup unsweetened shredded coconut in a shallow bowl.

Step 7

Cook the discs in 3 batches: Add the discs one at a time to the boiling water and cook until they float to the top, about 4 minutes Using a slotted spoon, return the cakes to the baking sheet and gently blot up some of the moisture with paper towels (do not pat completely dry).

Step 8

Place the cakes in the coconut one at a time, tossing until well coated all over. Place on a serving dish in a single layer and sprinkle with the sesame seed and sugar mixture.