Heat oil in a medium saucepan over medium-high heat. Add apple and 1/2 cup onion; sauté 7 minutes or until tender. Add cumin; sauté 20 seconds. Add 3/4 cup broth, 1/2 cup juice, vinegar, and 1/4 teaspoon salt; bring to a boil. Gradually stir in couscous. Remove from heat; cover and let stand 5 minutes. Fluff with a fork.
While couscous stands, heat a large nonstick skillet coated with cooking spray over medium-high heat.
Cut pork crosswise into 12 pieces. Sprinkle both sides of pork with 1/4 teaspoon salt and black pepper. Add pork to pan; cook 3 minutes on each side or until done. Remove from pan; keep warm.
Add 1/2 cup onion to pan, and sauté for 1 minute. Remove 1 chile from can; reserve remaining chiles and sauce for another use. Finely chop chile. Add the chopped chile, 3/4 cup broth, and 1/2 cup juice to pan, and bring to a boil. Cook 2 minutes or until sauce is reduced to 2/3 cup. Serve pork and sauce over couscous.