Rinse bean sprouts five times with water to clean them.

Place bean sprouts in a pot, add 1200ml water, and 0.5 tbsp salt.

Boil the bean sprouts for 8 minutes, then let them sit for 2 minutes without opening the lid.

Drain the bean sprouts and rinse them with cold water to make them firm.

In the bean sprout cooking water, add 1 green chili, anchovies, kelp, and garlic. Boil on high heat, then simmer for 5 minutes.

Strain the broth to remove solids, leaving only the liquid.

Clean the squid with flour and salt, then slice it into small pieces.

Add 300ml more water to the broth and bring it to a boil. Add the squid and cook until tender.

Add sliced green chili, red chili, and spring onion to the soup and simmer briefly.

Add the cooked bean sprouts back to the soup and season with 1 tsp salt.

Serve the soup in individual bowls or earthenware pots.