Piece together wafer paper, without overlapping, to fit bottom of a 9-by-13-inch baking pan, and set aside. Liberally sprinkle a clean surface with cornstarch. Pour egg whites into bowl of electric mixer fitted with the paddle attachment; set aside.
In a medium saucepan, combine honey and granulated sugar. Place over medium heat; cook until mixture just begins to simmer, about 4 minutes. Clip a candy thermometer onto the side of saucepan; continue to heat, stirring occasionally.
Beat whites until stiff peaks form; add confectioners' sugar, and beat until combined. When thermometer registers 315 degrees, remove honey mixture from heat. Temperature will rise to 320 degrees. Stir until temperature drops to 300 degrees, 1 to 2 minutes. With mixer running, slowly pour honey mixture into egg-white mixture (at this point, whites will double in volume; let stand a few seconds; volume will return to normal). Beat until mixture thickens and begins to stick to beaters; fold in the nuts.
Pour mixture onto cornstarch-covered surface; knead about 5 turns. Stretch and roll to fit pan; place mixture in pan. Cover with another layer of wafer paper; let cool on wire rack. Cut into slices while still warm; store in airtight container, with parchment between layers, for up to 2 weeks.