First start with the marinade: In a medium bowl whisk together the Lemon (1 teaspoon), Lemon (3 tablespoon), Sunkist Orange (1 teaspoon), Orange Juice (6 tablespoon).
Add Extra-Virgin Olive Oil (6 tablespoon), Whole Grain Mustard (3 tablespoon), Honey (6 tablespoon), Crushed Red Pepper Flakes (1/2 teaspoon), Garlic (3 clove), Fresh Thyme Leaves (1 tablespoon) and Salt (2 1/2 teaspoon) and whisk again.
Place the Bone-In Chicken Leg (4 pound), Carrot (3 cup), Yellow Onion (1), and Dried Dates (1 cup) in a large sealable plastic bag. Add the marinade and seal shut. Massage to make sure everything is evenly coated with the marinade.
Place the bag on a rimmed sheet pan to protect against leakage and marinate in the refrigerator for at least 6 hours or overnight.
Preheat the oven to 425 degrees F (220 degrees C) and set an oven rack in the middle position.
Transfer all the ingredients from the bag, including the marinade, to a rimmed sheet pan. Turn the chicken skin side up. Roast until chicken is lightly browned and cooked through, 40-45 minutes. Halfway through cooking, stir the carrots.
Turn on broiler, and cook 1-3 minutes more, or until the skin is golden brown and crispy. Watch carefully because the honey in the marinade can cause the skin to burn quickly!
Transfer the chicken, carrots, onions and dates onto a platter, along with the sauce in the pan. Sprinkle with Italian Flat-Leaf Parsley (2 tablespoon), Scallion (2), and Salted Pistachios (1/4 cup) over the top and serve.