Preheat oven to 350 degrees. Line a baking sheet with parchment paper or a silicone baking mat. Gather your ingredients so that you have everything close at hand on the counter or table.
In a small bowl, mix together the all-purpose flour, baking cocoa, baking soda and salt.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy, about 2 minutes.
Add eggs, one at a time, mixing well after each addition. Beat in the vanilla extract.
Gradually stir in the flour mixture until just combined. Add chocolate chips and sliced almonds.
The First Bake:
Scoop the dough onto the lined baking sheet and pat it into a flattened log about 13 inches long, 3 inches wide, and about 3/4" thick. Smooth out the top and sides using an offset spatula dipped in water. Bake in preheated oven for 25 minutes.
The Second Bake:
Remove from oven and reduce the oven temperature to 325 degrees. Spray the cookie log with water, spritzing the sides and top. This will soften the crust just enough to make slicing easier.
Wait five minutes, then carefully transfer the cookie log to a cutting board. Using a sharp knife, cut crosswise with knife making 1/2" slices.
Place cookie slices on baking sheet standing up on edge.
Bake for another 30-35 minutes, until biscotti feel very dry and crisp around the edges. Remove from oven and transfer to a cooling rack.
Dust with powdered sugar. Makes approximately 24 cookies.
*Unless otherwise indicated, all butter used on this recipe site is salted.