Preheat oven to 350º F.
Gently unfold or unroll prepared pie crust. With wet fingers, press together any cracks. Sprinkle flour on one side; place floured side down on a 9-inch pie plate. Flute the edges; prick the bottom. Bake at 350º F for 10 minutes. Remove from oven and increase heat to 400º F. Sprinkle crumbled bacon and Swiss cheese on bottom. Set aside.
In a saucepan, melt butter. Add leeks, parsley, salt, pepper and nutmeg. Sauté over medium heat for 3 minutes. Spoon mixture in prepared pie crust.
In a bowl, whisk eggs, half and half and milk until well blended and frothy. Pour over onion mixture. Bake at 400º F for 25 minutes or until nicely browned and puffy. Serve immediately. Yield: 6 servings.