Make pie crust recipe and transfer to a 7-in. pie plate; flute edge.
Line shell with a double thickness of heavy-duty foil.
Bake at 450° for 4 minutes.
Remove foil; bake until crust is golden brown, about 2 minutes longer. Cool on a wire rack.
In a small saucepan, combine sugar and eggs until well blended. Cook over low heat, stirring constantly, until mixture coats the back of a metal spoon. Remove from the heat.
Stir in chocolate and vanilla until smooth.
Cool until the mixture is lukewarm.
In a bowl, cream butter until light and fluffy.
Add cooled chocolate mixture; beat on high speed until light and fluffy, about 5 minutes.
In another large bowl, beat cream until it begins to thicken. Add confectioners' sugar; beat until stiff peaks form. Fold into chocolate mixture.
Pour into the crust. Chill for at least 6 hours before serving. Garnish with whipped cream and chocolate curls.