Lightly salt the 6 cups water; bring to boiling. Add noodles; cook according to package directions. Drain well; set aside. Meanwhile, spray a 10-inch skillet with nonstick spray coating. Cook onion in skillet until nearly tender. Add oil to skillet. Add chicken and cook for 3 to 4 minutes or until chicken is tender and no longer pink. In a small bowl stir together yogurt, flour, paprika, and salt. Add undrained mushrooms to skillet. Stir in yogurt mixture. Cook and stir until slightly thickened and bubbly. Cook and stir 1 minute more. Serve over hot noodles. Makes 5 servings.