Soak the soybeans for at least 8 hours.
Boil the soaked soybeans in boiling water.
Rinse the boiled soybeans in cold water, then blend them smoothly with water in a blender.
Strain the blended soybean liquid through a sieve for a fine texture.
Boil the chicken breast, let it cool, and shred it along the grain.
Julienne the cucumber, onion, and carrot.
Boil the somyeon noodles, then rinse them in cold water.
Place the somyeon noodles in a bowl and top with vegetables, shredded chicken breast, and cherry tomatoes.
Pour chilled soybean soup and chogye broth over the noodles.
Season to taste with mustard, vinegar, and salt.