1. In a large bowl, whisk together flour, baking powder, and salt. Set aside.

2. In a stand mixer, cream butter and superfine sugar on medium speed until pale and fluffy (2–3 minutes).

3. Add egg and almond extract. Mix just until combined.

4. Divide dough evenly into two portions. Tint one portion with red gel food coloring; leave the other plain.

5. Roll each dough portion between parchment sheets to 1/4-inch (0.6 cm) thickness. Chill for 1 hour.

6. Place the red dough sheet on top of the plain dough sheet. Trim edges to create a neat rectangle.

7. Lightly brush a bit of water between the layers to help them stick together.

8. Starting from one long edge, roll tightly into a log, pressing gently as you roll to remove air pockets.

9. Wrap the log tightly in plastic wrap, then parchment paper. Chill for 2 hours or overnight.

10. Preheat oven to 350°F (180°C). Line baking trays with parchment paper.

11. Let the chilled log rest at room temperature for 5–10 minutes before slicing.

12. Use a sharp, un-serrated knife to slice cookies 1/4-inch thick.

13. Place slices 2 inches apart on prepared trays and bake 11–12 minutes, until edges are set but centers are pale.

14. Cool on baking sheet for 5 minutes, then transfer to a wire rack to cool completely.