Arrange broccoli in even layer in 11 x 7 baking dish coated with cooking spray: set aside.
Combine milk, flour, salt and pepper in large saucepan over med-high heat; bring to a boil. Cook 1 minute until thick, stirring constantly. Remove from heat and add Laughing Cow & shredded cheese, stir until smooth. Stir in mayo & onion. Spoon evenly over broccoli.
Toss panko with melted butter and sprinkle over broccoli cheese. Dust with paprika. Bake at 375 for 25 minutes until lightly browned and begins to bubble. Let stand for 5 minutes before serving.