In a stand mixer, cream the butter and sugars together until light and fluffy. Add in the eggs and vanilla and beat until well incorporated.
In a small bowl, combine the flour, baking powder and salt, then gradually add that mixture to the egg mixture. Stir until just combined. Fold in the chocolate chips.
Turn the dough out onto a parchment lined baking sheet and shape into a 3” x 15” loaf (it should be somewhere around ¾” thick).
Bake at 350 for 25-30 minutes or until lightly browned. Remove from the oven and let cool for 30 minutes. Reduce the oven temperature to 325 degrees.
Once cool, slice the biscotti into 1-inch (ispieces and return to the baking sheet, cut side up. Bake for an additional 10 minutes. Flip them over and then bake for another 10 minutes.
Let them cool completely, then store in an airtight container for up to 5 days.