How to Make It
Preheat oven to 350°.
Cut tops off bell peppers; discard tops, seeds, and membranes. Cook peppers in boiling water 5 minutes; drain and set aside.
Coat a large nonstick skillet with cooking spray, and place over medium-high heat until hot. Add onion, mushrooms, celery, apple, and garlic; sauté 3 minutes. Remove from heat; set aside.
Combine broth, salt, cumin, pepper, and turmeric in a medium saucepan. Bring to a boil; stir in couscous and oil. Remove from heat; cover and let stand 5 minutes. Fluff with a fork. Add onion mixture, raisins, pine nuts, and parsley; stir well. Divide couscous mixture evenly between peppers. Place stuffed peppers in an 8-inch square baking dish; bake at 350° for 15 minutes.