Beef and Radish Soup (Soegogi Muguk – 쇠고기무국)

Ingredients (serves 2-3):

½ pound beef brisket, cut into small pieces
½ pound Korean radish or daikon, washed and peeled
2 green onions, sliced thinly diagonally
4 garlic cloves, minced
1 tablespoon fish sauce (or soup soy sauce)
1 teaspoon salt
7 cups water