Cut the chicken into 1/2-inch pieces and season all over with salt, to taste, and the five-spice powder.
In a large saute pan with high sides over medium-high heat, add the peanut oil.
When the oil is hot, add the whole garlic cloves and chile and saute until they are just starting to blacken. Remove and discard the garlic and chile, leaving the flavored oil.
Add the chicken to the pan and saute until golden but not cooked through. Stir in the bok choy and carrots and saute for 1 minute.
Stir in the mirin and cook for 30 seconds, then add the soy sauce and chicken stock and heat through. Ladle the soup into large, wide bowls and garnish with the chopped cilantro.