In another big stock pot, add 3 tbsp vegetable oil. Heat on medium high heat, then add star anise, cinnamon stick, shallot, ginger, and bay leaves. Sauteed for 5 minutes or until their fragrance is released.
Add sugar, dark soy sauce, light soy sauce, 2 cups of temper broth, and 2 cups of water. Stir to combine everything. Bring to boil then reduce the heat to medium high, simmer for 10 minutes.
Continue simmering master stock. Hold chicken leg at the top of the leg, ladle boiling soy mixture all over chicken leg. Set aside. Continue doing the same thing for the rest of the chicken legs.
When all chicken legs are all coated with soy sauce mixture (master stock), return them to the pot and simmer for another 20 minutes, partially cover the pot. Adjust the heat high enough to simmer the whole pot.
Chicken legs quarters should be done cooking after 20 minutes in master stock. If you're using whole chicken, it should be 30 minutes to cook in master stock.
Turn off the heat and let the chicken legs steep inside the pot for 15 minutes before serving.