Step 1

Preheat the oven to 350°F. Lightly grease (or line with parchment) a large baking sheet.

Step 2

In a medium sized bowl, use an electric mixer to beat the butter, sugar, salt, vanilla and baking powder until the mixture is smooth and creamy. Beat in the eggs; the batter may look slightly curdled. Lower the mixer speed, add the flour, cinnamon, chips and nuts (if using). Mix until smooth. The dough will be quite soft and sticky, but should hold its shape when you drop it from a spoon.

Step 3

Transfer the dough to the prepared baking sheet, shaping it into a rough log about 14-inches long, 2½ inches wide and ¾ inch thick.

Step 4

Bake for 25 minutes. Remove from oven and let cool on the pan anywhere from 5 to 25 minutes; just work it into the schedule of whatever else you're doing in the kitchen. Five minutes before cutting, use a spray bottle filled with room temperature water to lightly but thoroughly spritz the log, making sure to cover the sides as well as the top. Softening the crust just this little bit will make slicing the biscotti much easier.

Step 5

Reduce the oven temperature to 325°F. Wait another 5 minutes, then cut the biscotti into ¾ inch slices. Be sure to cut straight up and down. If you cut at an angle, the biscotti may be thicker at the top than the bottom, and they'll topple over during their second bake.

Step 6

Set the biscotti upright on the prepared baking sheet. Bake for 25 minutes. Remove from oven and transfer them to a rack to cool.