Juicy Blackstone Orange Chicken

Name: Juicy Blackstone Orange Chicken
Cuisine: Asian
Ingredients: Options for Substitutions; Estimated nutrition for the whole recipe (without optional ); Calories 2200-2400; Fat 100-120 g; Carbohydrates 200-220 g; 3 pounds boneless, skinless chicken thighs; 1-2 tablespoons avocado oil; 1 large bell pepper, chopped into bite-sized pieces; 1/2 small onion, chopped into bite-sized pieces; 1/2 medium orange, thinly sliced with seeds removed; Salt and pepper to taste; 1 cup orange juice; 2 tablespoons orange marmalade (such as smucker’s); 1/2 cup white sugar; 2 tablespoons soy sauce; 2 tablespoons rice vinegar; 1/2 teaspoon ginger, minced (squeezable type works well); 2 cloves garlic, minced; 1/2 teaspoon red pepper flakes