Rinse the soybeans thoroughly and soak them for at least 5 hours.
Boil the soaked soybeans in boiling water for 10 minutes.
Rinse the boiled soybeans with cold water, put them in a blender with water, and blend until smooth.
Strain the blended soybean mixture through a fine sieve to make it silky.
Pour the soybean milk into a pot and simmer over medium-low heat, stirring occasionally.
Place rice in a bowl and pour the cooked soybean broth over it.
Top with julienned cucumber, seaweed flakes, or your favorite garnishes to finish.