Line a large baking sheet with parchment paper. Set aside.
In a bowl, whisk together the cake flour and salt until no lumps remain.
In the bowl of a stand mixer fitted with the paddle attachment, cream butter and the Redpath® Golden Yellow Sugar on medium speed until pale in colour; 2 minutes.
Add in the egg yolk, pure vanilla extract, and peppermint extract. Blend until fully incorporated into the butter mixture.
Add in half of the dry ingredients. Mix on low speed until just combined. Repeat with the remaining dry ingredients. Mix on low speed until dough is no longer crumbly and holds together; do not overmix.
Using a 1 tbsp measuring spoon, scoop 1-inch balls (or around 15 grams) onto the prepared baking sheet. Roll each ball in the palm of your hand until smooth and roughly spherical. Space cookies about 2 inches apart on the baking sheet. With the handle of a wooden spoon dipped into a small dish of water (this prevents the handle from sticking to the dough), make an indentation into each ball (about ½-inch deep and wide).
Place baking sheet into the fridge to chill; at least 30 minutes. Preheat the oven to 375°F (191°C).
Place the chilled cookies into the preheated oven. Bake for 10 to 12 minutes or until bottoms and edges are golden in colour. Tops should still be relatively pale.
Allow to slightly cool on the pan before transferring to a wire cooling rack to cool completely.