In a 4-quart saucepan, melt butter over medium heat. Add onions, salt, pepper and thyme. Sauté 3 to 5 minutes, or until onions are softened.
Stir in broth, cream and pasta. Heat to boiling. Reduce heat and simmer 12 to 14 minutes, stirring occasionally. Stir in vegetables and turkey, cook 2 to 3 minutes or until pasta is tender and sauce is thickened. Stir in cream cheese until melted. Garnish with parsley, if desired.