In a medium bowl whisk together the all-purpose flour, baking powder, and salt until thoroughly mixed.
In the bowl of a stand mixer fitted with a paddle attachment, cream the Redpath® Special Fine Granulated Sugar and butter on medium-high speed until smooth and creamy; 2 to 3 minutes.
Scrape down the bowl and add in the egg, peppermint extract, and vanilla extract. Mix on medium speed until egg is fully incorporated. Scrape down the bowl as needed.
Add the dry ingredients in two additions. Mix on low speed until just combined; do not overmix.
Remove the dough from the bowl and divide it in half (approximately 260 grams per half) or by eye.
Pat and shape one of the halves into a flat, rectangular disc. Wrap well in plastic wrap and place into the fridge to chill.
Place the other half of the dough back into the bowl of the stand mixer and add 3 to 4 drops of red gel colouring to the dough. Mix on low speed until colour is homogenous. If a darker colour is desired, add more gel colouring until the desired colour is reached.
Remove dough from bowl and shape it into a flat, rectangular disc. Wrap well in plastic wrap and refrigerate for 20 minutes to make it easier to handle.
Remove the red dough from the fridge. Place the dough on a lightly floured piece of parchment paper. Lightly dust the top of the dough with flour and place another piece of parchment paper on top of the dough. With a rolling pin, roll the dough to a 10 x 8-inch rectangle. Place the dough onto a baking sheet and place it back into the fridge.
Remove the plain dough from the fridge. And repeat the process of rolling it out to a 10 x 8-inch rectangle with this piece of dough.
Remove the red rectangle from the fridge. Using a pastry brush, gently dust off any excess flour from the surface of the dough.
Brush off any excess flour from the plain rectangle. With the help of the parchment paper, lift and line up the edges of the dough with the red rectangle. Quickly flip the rectangle onto the red dough. With light pressure, gently smooth the plain rectangle onto the red rectangle, removing as many air bubbles as possible. Carefully peel away the parchment paper from the plain rectangle.
From one of the longer edges, tightly roll the dough lengthwise into a log. Cut the log in half. Wrap each log in parchment paper or plastic wrap. Place into the fridge to chill; at least 2 hours, or overnight.
Preheat oven to 350°F (177°C). Line a large baking sheet with parchment paper.
With a sharp chef’s knife, slice the log into ¼ inch rounds and place onto the lined baking sheet about 1 to 2 inches apart.
Place back into the fridge to chill; 10 minutes.
Place cookies into the preheated oven and bake until the centres of cookie are set; 6 to 8 minutes. Remove from oven and allow cookies to cool completely on the baking sheets.
Store completely cooled cookies in an airtight container lined with parchment paper for up to a week at room temperature or in the freezer for up to 2 months.