- With the rack in the middle position, preheat the oven to 170 °C (325 °F). Line a baking sheet with parchment paper or a silicone mat.
- In a bowl, combine flour, ground almonds, baking powder and salt. Set aside.
- In another bowl, cream butter and sugar with an electric mixer. Add eggs, one at a time until smooth. With a spatula, add dry ingredients and liqueur and stir until dough is smooth. Add almonds.
- On a generously floured work surface, divide dough into 4 pieces. With your hands, shape into four 25-cm (10-inch) long logs. Place logs on the baking sheet, spacing them evenly. Bake for about 30 minutes or until lightly browned. Let cool for 10 minutes.
- With a bread knife, cut each roll into 2-cm (3/4-inch) thick slices.
- Place cookies, standing up, on the baking sheet. Bake for 20 minutes or until golden brown and dry. Let cool completely. Delicious with coffee.
Keep cantuccini in an airtight container. If they soften, just dry them again for a few minutes on a baking sheet in a 170 °C (325 °F) preheated oven.