Sift the flour and cornflour over the butter mixture, and stir through with a wooden spoon till a soft dough is formed.
Add icing sugar along with the salted caramel sauce. Beat on low speed until combined and smooth.
Use a butter knife to spread a little buttercream on the base of a cooled biscuit, and sandwich it together with another biscuit. Repeat till all biscuits are made. This recipe will make about 18 - 20 biscuits. Nutrition has been calculated based on a serving size of 2 biscuits.
Icing sugar, powdered sugar, confectioner’s sugar, 10X sugar are all the same thing. What they are is granulated white sugar that has been pulsed to a powder, and then mixed with a small amount of cornflour (or cornstarch). Icing sugar tends to clump, so it’s always best to sift it before using. In case there are any clumps, just press it down with a spoon.
In case you don’t have any, it is possible to make your own - just pulse 1 cup of granulated white sugar in a spice grinder with 1 tablespoon of cornflour / cornstarch till a fine powder is formed.
There are types of icing sugar available in Australia - pure icing sugar which is just icing sugar pulverized into powder, and icing sugar mixture which is sugar pulverized into powder, mixed in with cornflour / cornflour.