Mix the dry ingredients - Flours, baking powder, sugar and salt.
make some "eggs" - Blend flax seeds (using a hand blender) with water (the ratio is 1:3, 1 tbsp flax seeds+3 tbsp water=1 "egg"). blending well breaks the seeds and lets out the gel inside them, if the ratio is correct and the seeds are not very old - you will get a texture that resembles the texture of beaten eggs. but it's thicker.
Add the wet ingredients to the mix and keep kneading until the dough ball is formed (don't over-knead).
Add the nuts and mix briefly until absorbed in the dough.
With wet hands, form 2 loafs of cookie dough and place on a baking pan.
Bake at 170 degrees C for 20-30 until golden brown. take the loafs out for a cool-down
Cut the loafs into Biscotti. I did it using a big knife and cutting at once to prevent the cookies from crumbling.
Re-arrange on the baking pan and bake at 150 Degrees for another 10-15 minutes. the Biscotti will dry further. keep in a closed jar.
This recipe was veganized and altered just a bit. the original recipe can be found in this excellent baking website (hebrew)
I'd love to get more feedback - questions about recipes, comments and suggestions!