In 3-quart saucepan, melt 1/4 cup butter over low heat. Stir in flour, mustard, salt and pepper. Cook over medium heat, stirring constantly, until mixture is smooth and bubbly. Remove from heat. Gradually stir in milk. Heat to boiling over medium heat, stirring constantly; boil 1 minute. Stir in cheese, 1/2 cup at a time, until melted. Remove from heat. Stir in uncooked macaroni. Gently stir in kale, tomatoes and bacon; pour into casserole.