Preheat the oven to 425ºF and grease a rimmed baking sheet with avocado oil.
Season the chicken with salt and pepper and place onto the prepared baking sheet. Bake at 425ºF for 40 minutes, or until cooked through and the skin is crisped.
While the chicken is cooking, combine the soy sauce, monk fruit, orange zest, lemon juice, vinegar, and miso in a small saucepan. Bring to a simmer over medium heat, stirring to dissolve the monk fruit. Simmer to reduce to a few tablespoons and remove it from the heat. Adjust seasoning to taste. Serve over roasted chicken.