This was super simple and delicious (found on allrecipes.com)!
4 large boneless, skinless chicken breasts, cubed
2 Tablespoons margarine
1 (0.7 oz.) package dry Italian-style salad dressing mix
1 can condensed cream of chicken soup
1 (8 oz) package cream cheese
Put chicken, margarine, and dressing mix in slow cooker; mix together and cook on low for about 5 hours.
Mix together cream cheese and soup, add to slow cooker and cook another 30 minutes until heated through.
Meanwhile, boil noodles as package directs.