Clean the chicken breast thoroughly and prepare it.
Cut radish, green onion, and garlic into bite-sized pieces.
Pour water into a pot and add the chicken breast, radish, green onion, and garlic.
Bring to a boil over high heat and skim off any foam.
Reduce to medium-low heat and simmer for 40 minutes.
Take out the chicken breast and shred it finely.
Strain the broth through a sieve to make it clear.
Place the chicken breast and broth in a bowl and season with salt and pepper.