Meanwhile, in large skillet, melt butter over medium-high heat. Add frozen carrots and onions; cook 3-4 minutes or until thawed. Sprinkle with flour; cook 1 minute, stirring constantly. Stir in chicken broth, milk and thyme. Bring to a simmer and cook 3-5 minutes until thick, stirring often. Add chicken and peas; cook 2-3 minutes or until heated through. Stir in parsley, salt and pepper. Let cool 5 minutes, then spoon mixture into prepared pan.