Preheat oven to 350 degrees. Line a baking sheet with parchment paper.
In a large mixing bowl, Add in the butter, granulated sugar, and brown sugar. Cream on medium speed until light and fluffy. It will take about 3 minutes.
Add in the eggs and vanilla extract. Mix until combined.
Sift in the flour, baking powder, salt, flour and chocolate chips. Stir into the butter mixture just until the dry ingredients are incorporated.
Dump the dough onto the parchment paper. Shape the dough into a 11 inch long and 6 inches wide log. Make sure the top is flattened out. It doesn't have to be exactly that, that's just the size of mine. You may need to flour your hands to prevent sticking.
Place the biscotti into the oven and bake for 30 minutes. Remove from the oven and let cool for 10 minutes. Keep the oven on though. We're not done with it.
Slice the bisocotti into 12 slices.
Roll the biscotti onto the first cut side. Place back into the oven for 10 minutes.
Flip the biscotti to the cut side and bake for another 10 minutes. Remove from the oven and let cool.