Preheat the oven to 190 C / Gas 5. Grease baking trays or line with parchment.
In a medium bowl, beat together the oil, eggs, sugar and anise flavouring until well blended. Combine the flour and baking powder, stir into the egg mixture to form a heavy dough. Divide dough into two pieces. Form each piece into a roll as long as your baking tray. Place roll onto the prepared baking tray, and press down to 1cm thickness.
Bake for 25 to 30 minutes in the preheated oven, until golden brown. Remove from the baking tray to cool on a wire rack. When The biscotti are cool enough to handle, slice each one crossways into 1cm slices. Place the slices cut side up back onto the baking tray. Bake for an additional 6 to 10 minutes on each side. Slices should be lightly toasted.