Preheat oven to 375~. Brown beef in skillet; drain off fat. Stir in taco seasoning mix and water, cover, and simmer (followlabel directions). Cool 10 minutes. Add cheese and chilies and mix well. Spoon into prebaked pastry shell. Combine eggs, cream, and salt; mix unti smooth. Pour over meat mixture. Bake in prehated oven for 40 to 45 minutes, or until custard is set and pastry is browned. Allow pie to stand 5 minutes before serving.