Fit one piecrust into 9-inch pie pan; flute edge.
Heat oven to 350°F. In medium-size saucepan, melt butter with 1 cup chocolate chips over low heat until smooth. Whisk in 1 cup sugar, the eggs, flour, salt and vanilla. Fold in remaining 1 cup chips; pour into pie shell.
Unfold remaining piecrust. Roll out to 14-inch circle. With 1-inch round and/or heart-shaped cookie cutter, cut out as many shapes as possible. Reroll scraps; cut more shapes. Overlap on top of pie, covering filling to edge. Brush cutouts with milk. Sprinkle with the 2 tablespoons sugar.
Bake in 350°F oven 40 to 45 minutes or until browned and set. If top gets too brown, loosely cover with foil about halfway through baking. Let pie cool on wire rack.
Beat cream and sugar until medium peaks form. Slice pie. Serve with whipped cream if desired.