Heat oven to 180ºC . In a medium bowl, beat eggs with an electric mixer on high speed until fluffy. Gradually beat in almond extract, vanilla and sugar until mixture is thick and lemon-colored, scraping down sides of bowl frequently with a rubber spatula.

Mix cake flour with baking powder and salt. With a wire whisk, fold into egg mixture until just thoroughly combined. Fold in pistachios.

Grease a 10x14 inch strip down center of two cookie sheets. Spoon half of pistachio mixture down center of each cookie sheet to make a 3x10 inch log. Bake 30 minutes. Remove from oven; leave oven on.

Let logs cool on sheets 5 minutes, or until cool enough to handle. With a serrated knife, cut each log diagonally into 16 slices. Place slices, flat sides down, on cookie sheet and return to oven. Bake 5 minutes. Turn slices over and bake 5-7 minutes, or until golden on both sides. Remove to racks and let stand until cool enough to handle. Spread melted chocolate over one end of biscotti and let cool completely.

Store in a tightly covered container. Makes 32 cookies.