Let's follow our camera to a ranch in Shih-tan township in Miaoli.

The owner uses local grown herb commonly known as Xiancao in Chinese in his chicken soup. Here on CTS, we'll uncover his secret recipe.

Inside the steamed pot is chicken soup. But the color is dark and the taste seems bitter.

It's no surprise some people dare not to take a sip.

But once you give it a shot, you'll be surprised by how delicious the soup actually is.

Guests who try the chicken soup are amazed by how sweet and fresh it is.

The secret weapon of the recipe is xiancao.

Without additional seasoning, the sweetness of chicken is retained and the soup tastes even sweeter because of the herb.

After being sun-dried for a year, the dried plant is to be rinsed and washed thoroughly in water, before being stewed in water for two weeks.

That's how the black soup is made.

Free range chicken is then added into the soup to be stewed for further hours.

Therefore the sweetness of the herb and the chicken is preserved at the same time.

For chicken soup lovers, it is a fresh dish.

But one should enjoy the soup when it's hot or it will be jelly-like when it gets cold.