In a medium pot, bring 4 cups of water to a rolling boil. Add 3 slices of ginger and 1 chopped scallion.

Gently lower the chicken drumsticks into the boiling water. Bring it back to a boil, then reduce heat to low and cover. Simmer for 10 minutes.

After 10 minutes, turn off the heat completely, leaving the chicken in the covered pot for another 15 minutes.

Ensure the chicken is cooked through by piercing it; juices should run clear.

Remove the chicken and place it in a bowl of ice water for 5 minutes. After cooling, shred the chicken using two forks.

In a saucepan over medium heat, warm 3 tablespoons of vegetable oil. Add the scallion whites and cook until crispy, about 2-3 minutes.

Combine the remaining oil with 2 tablespoons of light soy sauce, 1/2 teaspoon of sugar, and 1/2 cup of reserved cooking water. Bring to a gentle boil.

Add the minced ginger and chopped scallion greens to the sauce. Adjust seasoning to taste and pour over the shredded chicken to serve.