Japanese Nabeyaki Udon Soup

6 cups prepared dashi stock

¼ pound chicken, cut into chunks

2 carrots, diced

⅓ cup soy sauce

3 tablespoons mirin

½ teaspoon white sugar

⅓ teaspoon salt

2 (12 ounce) packages firm tofu, cubed

⅓ pound shiitake mushrooms, sliced

5 ribs and leaves of bok choy, chopped

1 (9 ounce) package fresh udon noodles

4 eggs

2 leeks, diced

Heat dashi stock, chicken, carrots, soy sauce, mirin, sugar, and salt in a pot over medium heat. Simmer until chicken is no longer pink in the center, 5 to 7 minutes. Add tofu, mushrooms, and bok choy, stirring until vegetables are tender, about 5 minutes more.

Stir udon noodles into broth and simmer until tender, 3 to 4 minutes. Add leeks and crack eggs into soup; simmer until eggs are slightly firm, about 5 minutes more.