Sprinkle salmon with 1/4 teaspoon salt and 1/4 teaspoon pepper. Heat 2 teaspoons oil in a large nonstick skillet over medium-high heat. Add salmon; cook 4 minutes on each side. Transfer to a plate, cool completely, and break into chunks.
Meanwhile, cook pasta according to package directions, adding beans during last 4 minutes of cooking time. Drain and rinse in cold water.
Place 1/4 cup oil, vinegar, anchovy paste, garlic, mustard, and remaining 1/4 teaspoon each salt and pepper in a jar. Cover and shake vigorously. Combine pasta mixture, salmon, and remaining ingredients. Toss with dressing.