How to Make It
In a large bowl, combine the chicken, 2 tablespoons of the oil, 2 scallions, half of the ginger, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Juice the lime over the top and toss to combine; set aside for 15 minutes.
Meanwhile, in a large saucepan, combine the rest of the ginger and the juiced lime half. Add an inch of water, place a large steamer basket (or large colander) in the pan, and bring to a boil. Remove the chicken from the marinade and place in the steamer in a single layer. Steam until cooked through, about 5 minutes, flipping once halfway through. Transfer to a cutting board and chop into 1/4-inch pieces.
Heat oven to 400º F. Lightly coat a 9-by-3-inch loaf pan with cooking spray and set aside.
In a large bowl, whisk together the eggs, mustard, 1 tablespoon of the tomato paste, remaining oil, and 1/4 teaspoon each salt and pepper. In a food processor, chop the garlic, onion, and carrot until finely chopped. Transfer to the bowl with the egg mixture. Add the chicken to the bowl along with the apple, breadcrumbs, and remaining scallions. Using your hands, mix to combine well. Place half the meat-loaf mixture in the pan. Sprinkle on the pistachios in 1 layer. Top with the remaining meat-loaf mixture, pressing gently. Bake for 20 minutes.
Meanwhile, whisk together the maple syrup and remaining tomato paste. Brush the glaze over the meat loaf and return it to the oven for 10 minutes. Remove and let rest, covered with foil, for 10 minutes before serving.