Preheat oven to 350 degrees F.  Line a 9-inch pie pan with either a homemade or a store-bought pie crust. Set aside.

In a large microwave-safe bowl, place margarine and broken-up semisweet chocolate bars.  Microwave on high for 1 minute.  Stir.  Melt again for 30 seconds and stir until mixture is smooth. (Microwave in 30 second increments if necessary.). Whisk in sugar, vanilla and salt until evenly combined.  Add eggs and whisk again until smooth. Pour into prepared pie crust.  Bake for 30 minutes or until a crust forms evenly across pie top.  Remove from oven and let cool on a wire rack for about 15 minutes before serving.  Serve with whipped cream, caramel sauce or vanilla ice cream.  Store pie covered in the refrigerator for up to a week.