1. Preheat oven to 375°.
2. To prepare chicken, combine the first 5 ingredients in a food processor. Add 2 peeled garlic cloves to cilantro mixture; pulse until finely chopped. Remove and discard giblets and neck from chicken. Starting at neck cavity, loosen skin from breast and drumsticks by inserting fingers, gently pushing between skin and meat. Pierce skin and flesh several times with a fork. Lift wing tips up and over back; tuck under chicken. Rub cilantro mixture under loosened skin and over breast and drumsticks. Place chicken, breast side up, on a roasting rack; place rack in a roasting pan. Place remaining 2 peeled garlic cloves on pan under chicken. Bake at 375° for 45 minutes or until a thermometer inserted in the meaty part of thigh registers 165°. Let stand 10 minutes. Discard skin.
3. To prepare sauce, place roasting pan on stovetop over medium-low heat. Add 1/2 cup broth to pan; bring to a boil, scraping pan to loosen browned bits. Squeeze roasted garlic cloves to extract pulp; discard skins. Strain broth mixture through a sieve into a small saucepan; discard solids. Add flour, stirring well with a whisk; bring to boil. Cook 1 minute, stirring constantly. Remove from heat. Stir in 1 teaspoon maple syrup and 1/8 teaspoon black pepper.
4. To prepare stuffing, cook bacon in a large nonstick skillet over medium heat until crisp. Remove bacon from pan; crumble. Add onion, ginger, and 2 minced garlic cloves to drippings in pan; cook 3 minutes or until lightly browned, stirring frequently. Stir in chard and mushrooms; cook 5 minutes or until chard wilts. Add crumbled bacon and rice; cook 30 seconds, stirring constantly. Stir in 2 3/4 cups broth; bring to a boil. Cover, reduce heat, and cook 45 minutes or until the rice is just tender and liquid is nearly absorbed. Add squash and 1 tablespoon maple syrup to pan; cover and cook 10 minutes or until squash is tender. Stir in 1/4 teaspoon black pepper. Sprinkle with walnuts.