Shortbread

Grease a 20cm square baking dish with cooking spray or butter.

In a stand mixer with the beater attachment, beat the butter and sugars vigorously until smooth.

Gently beat in the egg yolks.

Add the flour and salt and mix just until the dough comes together (Don't over-mix now).

Using damp hands, press the dough in an even layer in the pan.

Bake at 160°C for 40 to 45 minutes or until a thin, golden brown layer forms on top.

Allow to cool completely before cutting into two even columns and then six even rows.