In food processor, grind almonds into a very fine flour. Add powdered sugar, then pulse together a few times to break up clumps.
Add egg white and almond extract and process for about 1-2 minutes until the mixture looks smooth and combined and forms a single mass.
Lightly dust a smooth surface with powdered sugar. Then turn the almond paste mixture out onto the surface and gather into a ball. Roll into a log shape that's about 2" in diameter. Wrap in plastic wrap and allow to chill for at least 1 hour, up to one week. Makes 16 oz.
