Wash 4 pieces of boneless chicken thighs. Then, trim the fat and cut the chicken thighs into chunks.
Put the cut chicken thighs into a bowl. Add ⅛ teaspoon of salt, ⅛ teaspoon of white pepper, ½ teaspoon of garlic powder and 1 teaspoon of sesame oil into the bowl. Mix it well and let it marinate for at least 15 minutes. After, put ½ cup of rice flour, ½ cup of all purpose flour, 1 egg and ¾ cup of water into a mixing bowl.
Use a whisk to mix the batter very well.
Next, add the marinated chicken into the batter.
Mix well and cover the marinated chicken with batter.
Pour 4 cups of vegetable oil into the wok and turn the fire to small. Heat up the oil until it's hot enough. Also, you can use a thermometer, the temperature is around 350 F. Or, use a wooden chopstick to dip into the oil when you see some bubbles around the chopstick. It is a sign to show the oil is hot enough for deep fry.
Slowly add the chicken covered with batter into the oil.
Let it deep fry until it's slightly golden. Take out the chicken and turn the fire to medium small.
Double deep fry the chicken. The temperature of the oil is around 375F and put the fried chicken into the oil again.
Until the chicken is golden brown. Drain the chicken and put them on a paper towel to absorb excess oil.
Grate 2 slices of ginger.
After that, grate 2 cloves of garlic.
In a container, add ¼ cup of white sugar, ¼ cup of brown sugar, ¼ cup of orange juice, ¼ cup of vinegar and 2 tablespoons of soy sauce. Mix the sauce very well.
Next, pour 1 teaspoon of vegetable oil into the wok. Turn on fire to medium small. Add the grated ginger and garlic. And, ¼ teaspoon of crushed red pepper (chili pepper flakes). Stir fry them a little bit.
The following, pour the sauce mixture from step 14. Stir them a little bit.
Then, add 1.5 tablespoons of cornstarch and 2 tablespoons of water into a small container. Mix them well.
Pour the cornstarch mixture from step 17 into the sauce. Keep stirring the sauce.
When the sauce thickens, add the deep fried chicken into the sauce. Toss it and make sure the chicken is covered with the sauce.
Lastly, slice half of an orange and put them on the orange chicken as decoration.