Meanwhile, melt butter in a skillet over medium-high heat. If using chicken, add chicken, and sauté until cooked through; next add garlic to pan and sauté 1 minute. Combine broth and cornstarch in a small bowl; stir until well blended. Add broth mixture to pan; bring to a boil. Cook 1 minute or until thick, stirring constantly. Remove from heat. Stir in cream, juice, capers, salt and pepper. Add pasta mixture to broth mixture; toss gently to coat.