Thaw fish, if frozen. In a 2-quart baking dish combine 1 tablespoon of the olive oil, 1 tablespoon of the balsamic vinegar, and the cracked pepper. Place fish in the mixture; turn to coat both sides. Marinate at room temperature for 10 minutes.
Measure thickness of fish. Place the fish on the unheated rack of a broiler pan; broil 4 inches from the heat just until fish flakes easily with a fork. (Allow 4 to 6 minutes per 1/2-inch thickness of fish.) Turn fish after half of broiling time.
Meanwhile, in a large saucepan cook buckwheat noodles about 4 minutes or whole wheat noodles 8 to 10 minutes, or until just slightly chewy. Drain; place in a large bowl. Add remaining olive oil, remaining balsamic vinegar, orange juice, chopped orange, garlic, onion, and crushed anise seed; toss to coat. Divide noodle mixture among 4 dinner plates. Top each serving with a piece of salmon. Garnish each serving with fresh fennel leaves, if desired. Makes 4 servings.