Preheat your oven to 400℉ and prepare a baking sheet by lining it with parchment paper.
In a medium bowl, whisk together your flour, baking powder, and salt.
In a large bowl, using a hand mixer, whip together your butter and sugar until it is light and fluffy.
Mix in your eggs, vanilla extract, and almond extract. Whip together.
With the mixer on low speed, add in your flour mixture, about ¼ cup at a time. Mix until just combined.
Finally, fold in your sliced almonds.
On a lightly floured surface, shape your dough into a rough square.
Cut the dough into 4 evenly sized rectangles and roll each rectangle into 6-inch long logs and place on the prepared baking sheet, evenly spaced so the logs aren’t touching.
Bake at 400℉ for 20 to 25 minutes. Logs should be a light golden color.
Remove from the oven and allow to cool for only 5 minutes.
Lower oven temperature to 325℉, cut each log into about 1-inch slices, lay the slices flat on the sheet pan and return to the oven.
Bake for an additional 15 to 20 minutes. The biscotti should feel dry and be very golden.
Remove from the oven and cool on a cooling rack until they have reached room temperature and enjoy!
Optional: For a lovely garnish, you can dip the biscotti in some chocolate, or drizzle on top!