To prepare herb jus, combine first 4 ingredients in a saucepan over high heat. Bring to a boil; cook until reduced to 1/4 cup (about 8 minutes). Add fennel and broth. Bring to a boil. Reduce heat; simmer until reduced to 2 cups (about 30 minutes). Add 1 teaspoon thyme, chopped basil, and rosemary; simmer 5 minutes. Add 1/4 teaspoon salt and 1/4 teaspoon pepper.
Preheat oven to 375°.
To prepare salmon, heat oil in a nonstick skillet over medium-high heat. Add 1/2 cup shallots and 2 minced garlic cloves; sauté 1 minute. Add mushrooms; sauté 2 minutes. Add sherry; cook 4 minutes or until most of liquid evaporates. Remove from heat; cool completely. Stir in fontina, shredded Parmesan, and 2 teaspoons thyme. Cut 1 (3/4-inch-deep) diagonal slit from the center of 1 fillet; cut another slit in the opposite direction to form an X. Pull back salmon to form a pocket. Repeat with remaining fillets. Stuff 1/3 cup cheese mixture into each pocket. Place fillets on a jelly-roll pan coated with cooking spray. Drizzle with white wine, and sprinkle with 1/4 teaspoon salt and 1/4 teaspoon pepper. Bake at 375° for 15 minutes or until the fish flakes easily when tested with a fork. Serve with herb jus and Hazelnut-Herb Couscous; sprinkle with shaved Parmesan and parsley. Garnish with basil sprigs, if desired.