How to Make It
Cook pasta according to package directions, omitting salt and fat. Drain; keep warm.
Place chicken between 2 sheets of heavy-duty plastic wrap; pound to an even thickness using a meat mallet or small heavy skillet. Sprinkle chicken with 1/4 teaspoon salt and pepper. Place flour in a shallow dish; dredge chicken in flour, shaking to remove excess.
Heat 1 tablespoon butter in a large nonstick skillet over medium-high heat. Add chicken; cook 3 minutes on each side or until done. Remove chicken from pan; keep warm.
Melt 1 tablespoon butter in skillet over medium-high heat. Add garlic, leek, and remaining 1/4 teaspoon salt; sauté 4 minutes. Add broth and juice; cook 2 minutes or until liquid is reduced by half. Remove from heat; stir in remaining 1 tablespoon butter. Add pasta to leek mixture; toss well to combine. Serve chicken over pasta mixture; sprinkle with parsley.