140 g unsalted butter, very soft + more for greasing
demerara sugar
60 g browned butter, soft
0.75 tsp kosher salt
140 g toasted sugar (see recipe below)
255 g all-purpose flour
50 g cornstarch
Instructions
Brush a lasagne form with a light coating of soft butter. Add 1-2 tablespoons of demerara sugar and tilt the pan until it is well coated.
Preheat the oven to 150°C (300°F).
Combine butter, browned butter, salt, and toasted sugar in the bowl of a stand mixer. Mix well for 2-3 minutes.
Meanwhile, combine the flour and cornstarch in a bowl. Whisk well to combine.
Add half of the dry ingredients and continue mixing the ingredients for 30 seconds. Then add the remaining dry ingredients and mix until a crumbly dough forms.
Transfer the dough to the prepared pan and gently press it into the sides and corners of the tray.
Top the shortbread with a generous sprinkling of more demerara sugar.
Bake for 1 to 1.5 hours or until the top is set and has become lightly golden.
Allow the shortbread to cool for 10-15 minutes.
While still warm, cut the cookies to the desired size using a thin knife.
Allow the cookies to cool in the pan for a minimum of 4 hours or up to overnight.
Once the cookies are completely cooled, serve with your choice of warm beverage or cover in plastic wrap. The cookies can be kept at room temperature for up to 2 days.