Preheat the oven to 350 F and prepare a baking sheet
Mix all the dry ingredients except the walnuts together in a medium bowl.
In a large bowl, beat the wet ingredients together.
Add the dry ingredients in batches, mixing well after each addition
Stir in 1 cup of the walnuts.
The mix will be more like a thick batter than a dough. Pour onto a baking sheet and form into a loaf shape. It will spread a little but don't panic.
Bake for 30 minutes.
Remove from oven and reduce the temperature to 250 F.
Let the biscotti cool slightly then cut into slices. I cut my slices in half, too.
Arrange the biscotti with one of the cut sides down on the baking sheet and bake for another 40 - 45 minutes, turning over about halfway through. Keep an eye on the biscotti and remove them earlier if necessary.
To glaze the biscotti, mix the confectioner's sugar and the water to get a nice consistency. I rolled the biscotti in the glaze to coat all the sides, but you can drizzle, dip or frost as you like. Sprinkle the walnuts on top. The glaze will help them to stick.