Preheat your oven to 350°F (175°C) and line a large baking sheet with parchment paper.
In a medium bowl, whisk together the all-purpose flour, almond flour, baking powder, and salt until well combined.
In a large mixing bowl, beat the eggs and granulated sugar on medium-high speed for about 3 minutes until the mixture is pale and thick.
Whisk in the melted butter, vanilla extract, and almond extract until fully incorporated.
Gradually add the dry ingredients to the egg mixture, stirring with a heavy spatula until a stiff, sticky dough forms.
Fold in the whole toasted almonds until evenly distributed.
Divide the dough into two equal portions. On the prepared baking sheet, shape each portion into a log approximately 12 inches long and 2 inches wide, leaving space between them.
Bake for 25 to 30 minutes, or until the logs are firm and the tops are cracked and lightly golden.
Remove from the oven and let the logs cool on the pan for at least 15 minutes. Reduce the oven temperature to 325°F (165°C).
Transfer the logs to a cutting board. Using a sharp serrated knife, cut the logs on a diagonal into 1/2-inch thick slices.
Place the slices back onto the baking sheet, cut-side down. Bake for 10 minutes, then flip the slices over and bake for another 10 minutes until they are dry and toasted.
Transfer to a wire rack to cool completely. The biscotti will reach their final 'snap' texture once fully cooled.