Preheat oven to 350 degrees and butter a large cookie sheet.

Cut the orange into half and each half into quarters (including the rind.) Process the orange chunks in a food processor until it breaks down (the rind will be in larger pieces than the pulp.) You will have about 3/4 cup of processed orange. Set aside.

In a large bowl with an electric mixer beat eggs and sugar until light and creamy. Add the processed orange and vanilla and beat until fluffy, about 5 minutes. Add butter and stir.

In a smaller bowl sift together the flour, baking powder, baking soda, and salt. With a wooden spoon add and stir the dry ingredients into the egg mixture (the dough will be stiff.) Stir in the cranberries and pistachios until well combined.

On the buttered cookie sheet, place 3 evenly sized long mounds of dough. With wet hands (to prevent sticking) shape and form the dough into 3 slightly flattened logs about 12 inches in length and 3 to 4 inches wide.

Bake the logs in the middle of the oven until golden, about 30-35 minutes (depending on your oven.) Place the cookie sheet on a rack and allow to cool for 10 minutes.

Transfer the logs to a cutting board and with a serrated knife cut each log at an angle crosswise into 14 to 16 slices.

Arrange slices (laying down) on the cookie sheet (you will not have room for all the sliced logs at one time.) Bake for 7-8 minutes, turn the slices over and bake another 5-6 minutes. Transfer the biscotti to a rack and cool. Repeat until all sliced biscotti have been baked twice.

Store in an airtight container at room temperature for 10 days or place cooled biscotti in freezer bags and freeze for 3 months. Biscotti do not require thawing therefore may be eaten frozen.