1. Cook pasta according to package directions, omitting salt and fat. Drain and keep warm.
2. Heat a grill pan over medium-high heat; coat pan with cooking spray. Sprinkle fish evenly with 1/4 teaspoon salt and 1/8 teaspoon pepper. Add fish to pan; cook 3 minutes on each side or until fish flakes easily when tested with a fork.
3. Combine remaining 1/4 teaspoon salt, remaining 1/8 teaspoon pepper, shallots, and next 4 ingredients in a small bowl, stirring well. Slowly add oil, stirring constantly with a whisk. Drizzle shallot mixture over pasta; toss well to coat.
For baby: Omit black pepper. Shred the fish into bite-sized pieces. Serve fish and a spoonful of orzo mixture in a small bowl or on a rimmed plate.