Combine the softened butter and superfine sugar in a large mixing bowl, then beat with a spatula or hand mixer until the mixture is light, creamy, and slightly paler in color, about 2-3 minutes, filling the kitchen with a sweet, buttery aroma.
Gently fold in the sifted all-purpose flour, a pinch of smoked sea salt, and vanilla extract, mixing just until the dough begins to come together and feels soft but not sticky, resembling thick cookie dough.
Turn the dough out onto a lightly floured surface and gently knead it a few times to bring it together into a smooth ball. Wrap in plastic wrap and refrigerate for 15-20 minutes to make it easier to roll out.
Once chilled, unwrap the dough and roll it out evenly to about 1/4 inch (0.6 cm) thickness using a rolling pin, aiming for a smooth, flat surface with no cracks or cracks just beginning to form.
Cut the dough into your desired shapes using a cookie cutter or knife, then carefully transfer the cut cookies onto a parchment-lined baking sheet, leaving space between each for spreading. Chill the cut cookies for 10 minutes to help them hold their shape during baking.
Bake in a preheated oven at 160°C (320°F) for about 15-18 minutes, or until the edges are a light golden brown and fragrant. You'll notice a rich, buttery smell filling the air as the cookies develop their delicate crust.
Remove the baking sheet from the oven and let the cookies rest for about 5 minutes, allowing them to firm up slightly. Then, transfer the cookies to a wire rack to cool completely, which helps preserve their crumbly texture.
Once cooled, serve the cookies immediately or store them in an airtight container at room temperature for up to a week. Their crumbly, melt-in-your-mouth texture and smoky salt flavor make them a delightful treat anytime.
