Rinse 2 cups (400 g) of short-grain rice under cold running water for 1 minute to remove surface starch.

Steam the rinsed rice with 2 cups of water for 45 minutes, using a rice cooker or pot, until tender and slightly sticky.

Spread the cooked rice on a clean plate and cool to room temperature for 30 minutes.

Clean a 2 to 3 liter glass jar with hot water and dry completely.

Transfer the cooled rice to the jar, add 1 cup of filtered water, and sprinkle 1 teaspoon of koji spores evenly over the rice. Stir to combine.

Cover the jar with cheesecloth secured by a rubber band and let stand at 68–75°F (20–24°C) for 2 to 3 days without disturbing.

In a small bowl, activate 1/4 teaspoon yeast in 1/4 cup lukewarm water for 5 to 10 minutes until foamy.

Add the yeast mixture and the remaining 2 cups of water to the jar, stir thoroughly, and cover again with cheesecloth.

Ferment at 68–75°F (20–24°C) for 7 to 10 days, stirring once daily.

Starting on day 7, taste daily until you achieve a natural sweetness, gentle fizz, and slight tartness.

Line a strainer with cheesecloth over a bowl and strain the fermented mixture, gently squeezing out the liquid.

Using a funnel, bottle the makgeolli, leaving 1 inch of headspace for carbonation.

Refrigerate bottles to slow fermentation and store for up to 3 weeks, gently stirring or shaking before serving to redistribute sediment.