Make the Black Sesame Sugar:

Preheat oven to 400ºF (200ºC). Rinse black sesame seeds under running water, drain well, and spread evenly on a baking sheet.

Toast in the oven for 15–17 minutes, stirring every 3–4 minutes, until seeds are fragrant and crush easily between fingers.

Let cool completely.

Grind in two batches with granulated and brown sugars in a spice grinder until mixture resembles very fine cornmeal. Store in an airtight container in the fridge.

Make the Sticky Rice Dough:

Mix flour & sugar in a large bowl.

Pour hot water into the flour mixture and stir with a fork until lumpy.

Add vegetable oil and 1 tbsp cold water. Knead by hand until a soft, pliable, non-sticky dough forms. Add a bit more water or flour as needed.

Cook a small portion: Break off 1/5 of the dough, flatten, and microwave for 40–50 seconds until semi-translucent.

Knead cooked dough back into the rest until smooth and elastic.

Shape and Cook the Rice Balls:

Roll dough into a log and cut into 1 tsp-sized pieces. Roll into balls.

If not cooking immediately, dust with rice flour and freeze in an airtight container.

To cook: Bring a pot of water to a boil. Add balls and stir gently. Once they float, cook for an additional 2–3 minutes until puffed.

Drain and serve: Transfer to a bowl, sprinkle with a few tablespoons of black sesame sugar, and gently toss until the sugar melts into a glossy coating.