Preheat your oven to 400°F (200°C).
Pat the chicken thighs dry with paper towels to help them get crispy.
Rub the thighs with olive oil, salt, pepper, garlic powder, and onion powder.
Place the thighs on a baking sheet lined with baking paper or in a baking dish.
Bake in the preheated oven for 35-40 minutes, or until the internal temperature reaches 165°F (74°C) and the skin is crispy.
In a small saucepan over medium heat, combine the orange juice, orange zest, soy sauce (or coconut aminos), apple cider vinegar, sweetener, ginger, and garlic.
Bring to a simmer and cook for about 5-7 minutes, stirring occasionally.
Sprinkle the xanthan gum into the sauce while whisking continuously to avoid clumping. Continue to cook until the sauce has thickened.
Remove from heat and stir in the butter until melted and the sauce is smooth.
Once the thighs are done baking, remove them from the oven and let them rest for a few minutes.
Toss the thighs in the orange sauce until they are well coated.
Serve the orange chicken thighs hot, garnished with additional orange zest or chopped green onions.