Chocolate Chunk Biscotti

Preheat oven to 350°F. In a large bowl, whisk flour, cocoa powder, sugar, baking powder, and salt. In a small bowl, lightly blend eggs and vanilla. Add eggs to flour mixture and beat until almost combined. Add chocolate chunks and stir. Turn out dough on a lightly floured surface and divide in half. With floured hands, roll each half into a log about 15 inches long, then place on a parchment-lined cookie sheet. Flatten dough to about two-and-a-half-inches wide by one-inch tall. Bake for 25 minutes until dough is slightly firm. Remove from oven, and reduce heat to 325°F. Allow biscotti to cool for 20 minutes, then cut into half-inch slices with a serrated knife. Arrange on two parchment-lined cookie sheets and bake about 20 minutes, until crisp. Allow to cool.