heat, stirring constantly, until the mixture boils and thickens. Remove from the heat and stir in the walnuts. Turn the mixture into the pastry-lined pie plate and dot with the butter. Roll out the remaining pastry to an 11-inch circle. Place the top crust over filling and trim the edge to 1-inch beyond the rim. Fold the top crust under the bottom crust and form a ridge. Flute the edge and cut steam vents in the top crust. Bake in a preheated 400 degree F. oven for 30 minutes or until the crust is a golden brown and the filling is bubbly. Cool on a wire rack. ----