In a non-stick pan heat 1 tablespoon oil. Cook the chicken thigh on medium-high heat for 4-5 minutes on each side.
Mix Fresh Orange juice, ginger, sugar, soy sauce, red chili flakes, salt, and pepper.
Pre-heat the slow cooker on high heat for 20 minutes. Then add chicken thigh and orange juice mixture.
Cover and cook on high for about 2 hours. Stir a couple of times in between, to make sure the juice is evenly soaked by all the chicken thighs.
At the end of 2 hours, make a mixture of cornstarch and water. Pour it into the slow cooker. Mix well with a spatula.
Then add chopped red bell pepper. Give everything a good stir and cook on high for another 45 minutes to 1 hour.
While serving garnish with chopped green onions.