I actually baked biscotti in December as a Christmas gift for friends. I used essentially the same recipe then as I did now, so I had a better idea of what I was doing and they turned out better than before. The recipe is Sarah Moulton's Raisin Almond Biscotti found here, be prepared to spend some time on it. (That's why it's a biscotti process.) I follow it pretty closely except I find that 3 eggs is inadequate to bring the dough together and 1 whole egg is too much eggwash.
Basically, my modifications to the recipe this time include:
-soaking the raisins in the juice of one orange (instead of Cointreau, which I'm sure is lovely, but. . . expensive).
-adding the zest of 1 orange with the eggs and vanilla for even more orange flavour
-using 4 large eggs instead of 3 to bring the dough together
-only using as much eggwash as seems necessary
These are my two just golden, shiny (eggwash!) biscotti logs after their first half hour bake in a 325 F oven:

It's important to shape the logs very square so the ends won't result in undersized cookies. I did a much better job cutting uniform slices this time for more beautiful slices. It's best to cut straight a cross, not on an angle. I think I made that mistake last time.
Slices reveal a pretty yellow tinge from the zest/egg combination:


I actually ate many of the biscotti I made in December myself. A biscotti and a cup of (decaf) tea was a remarkably effective (and pleasurable) relaxation ritual before bed during the exam time.