Preheat the oven to 350°F. Butter a 9-inch pie plate.
In the top of a double boiler, melt the chocolate over boiling water. Remove from the heat and stir in the butter until blended. Add the remaining ingredients and mix until blended. Pour the mixture into the pie plate and bake about 35 minutes; the top of the pie will crack when its done but be careful not to over bake. Cool at least 10 minutes before trying to cut and serve. Serve with sweetened whipped cream.