Preheat the oven to 350°F or 180°C and line a baking sheet with a parchment paper.
In a bowl whisk together the flour, almond flour, baking powder, baking soda and 1/2 tsp salt.
In another large bowl, using an electric mixer or in your stand mixer beat the sugar and butter for 2-3 minutes until light and fluffy.
Then add the eggs one at a time and vanilla extract and continue to beat on low until combined.
Add the chopped pistachios and cardamom powder and flour to the butter-egg mixture.
Slowly stir with a spatula to form a soft, sticky dough.
Now using floured hands, shape the dough into 15inch x 3inch loaf on the the parchment paper.
Now bake the loaf in the preheated oven for 25-30 minutes or until golden brown. Let the loaf sit for about 10-15 minutes or so or until cool enough to handle.
Now decrease the heat of the oven to 150 C.
Transfer the loaf to a work surface and using a serrated knife, cut logs on diagonal into 1/2inch to 3/4inch wide slices.
Arrange the slices on the large cookie sheet. Bake for another 25-30 minutes turning once. bake until it looks nice golden brown and toasted.
Let the biscotti cool right on the cookie sheet.
Store the biscotti in an airtight container, they will keep up to 6 weeks or they can last for many months in the freezer.