1. Sprinkle fish evenly with salt and 1/8 teaspoon pepper. Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Add 2 fillets to pan; sauté 1 1/2 minutes or until browned. Carefully turn fillets; sauté 1 1/2 minutes or until fish flakes easily when tested with a fork or until desired degree of doneness. Place fillets on a plate; keep warm. Repeat procedure with cooking spray and remaining fillets.
2. Melt butter in pan; cook 2 minutes or just until lightly browned. Add shallots to butter; sauté 45 seconds, stirring frequently. Remove from heat; stir in remaining 1/8 teaspoon pepper, capers, and fresh lemon juice. Serve with fish.