With rack placed to center position, preheat oven to 350ºF.
Line baking sheet with parchment paper.
In a medium bowl, sift together the flour, baking powder and salt, set aside.
In a large bowl, mix the sugar with cooled melted butter, 3 lightly beaten eggs, vanilla extract and ground aniseed.
Add dry ingredients mixture to the egg mixture and stir thoroughly with a wooden spoon until well combined.
Add toasted almonds and mix in gently until well combined and almonds are evenly distributed.
Divide dough in half.
With hands lightly floured, shape each dough half into 2, 13 1/2" long, 2 1/2"wide logs.
Place both logs onto prepared baking sheet, spaced apart evenly.
Whisk egg white in a small nonreacive bowl until foamy. Brush over top and sides of the logs.
Bake logs for about 30 minutes, or until golden (they will spread out slightly)
Don't turn off the oven yet!
Place baking sheet on a rack and cool completely, about 25 minutes.
Transfer logs to a flat workspace. Remove and discard parchment paper.
Using serrated knife, cut logs on the diagonal into 1/2" wide slices.
Arrange slices, cut side down on same baking sheet.
Bake 10 minutes, until dry and "toasty" to touch. Turn biscotti over; bake until just beginning to color, about 7-8 minutes more.
Transfer to rack and cool.