Rich chocolate biscotti

Method
Prep:30min  ›  Cook:37min  ›  Extra time:5min  ›  Ready in:1hr12min 

1. Preheat oven to 190 C / Gas 5. Line 2 baking trays with parchment.
2. Combine vanilla extract and espresso powder in a small bowl; mix until espresso powder is dissolved.
3. Sift flour, cocoa powder, baking powder and salt into a bowl; mix in chocolate chips.
4. Whisk vanilla mixture, sugar, eggs and oil together in a large bowl. Add flour mixture; stir, by hand if needed, until dough comes together and is thick and stiff.
5. Divide dough into 2 equal pieces and place onto the baking trays. Shape each piece into a log (the same length as the baking tray); press down with wet hands to about 1cm thickness.
6. Bake in the preheated oven until firm, about 25 minutes. Remove from oven and cool until easily handled, about 5 minutes.
7. Move cooled logs to a cutting board and cut into slices with a serrated knife. Return the slices to the baking trays, placing them on their sides.
8. Bake until dry, about 6 minutes per side. Remove from oven and let cool until hardened on wire racks.