Melt butter, and let cool.
Beat egg yolks and egg at medium speed with an electric mixer until thickened. Add sugar and almond paste, and beat well. (Filling will be slightly lumpy.) Add cooled butter, beating just until blended.
Fit piecrust into a 9" pieplate according to package directions; fold edges under, and crimp.
Stir jam well, and spread in bottom of pastry. Stir filling, and pour over jam.
Bake at 325º for 45 minutes or until set and a golden crust has formed on top, shielding edges with aluminum foil after 30 minutes to prevent excessive browning. Cool completely on a wire rack. Serve at room temperature. Dust with powdered sugar before serving, if desired. Store in refrigerator.