1. Preheat grill to high heat.
2. Arrange onion slices and bell peppers on a grill rack coated with cooking spray. Grill onions for 12 minutes, turning after 6 minutes. Grill bell peppers 12 minutes, turning occasionally. Remove onions and bell peppers from grill, and let stand for 5 minutes. Slice onion rings in half. Thinly slice bell peppers; discard stems and seeds. Combine onion, bell peppers, 1/4 teaspoon salt, and 1/8 teaspoon black pepper in a small bowl. 3. Sprinkle fish evenly with remaining 1/2 teaspoon salt and remaining 3/8 teaspoon black pepper. Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Add fish to pan, and cook for 3 minutes on each side or until fish flakes easily when tested with a fork or until desired degree of doneness. 4. Warm tortillas according to package directions. Divide fish, onion mixture, and jalapeño slices evenly among tortillas. Serve with lime wedges, if desired. For more great recipes, check out " Debbie Macomber's Cedar Cove Cookbook."