Parboil the chicken drumsticks in water for 5 minutes. Drain and rinse to remove impurities.
In a small bowl, mix all the sauce ingredients until well combined.
In a large pot, add the chicken and 2.5 cups of water. Stir in the prepared sauce.
Bring to a boil over medium-high heat.
Reduce heat to medium-low and simmer for 15 minutes.
Add the potatoes, onion, and carrot. Continue simmering for another 15–20 minutes, or until the chicken is tender and the vegetables are cooked through.
Add the pre-soaked sweet potato noodles and cook until softened and tender (about 5–7 minutes).
Garnish with chopped green onions before serving.