This is the right recipe, you can knead this with your hands or use a foodprocessor and spend five minutes.
You can also substitute macadamia nuts with almonds.
Makes 18 biscuits
200gr (0.9cup – 7.2oz)flour
110gr (0.49cup – 3.9oz) sugar
130gr (0.6cup – 4.8oz) butter
1 egg yolk
1tsp vanilla extract
100gr (0.44cup – 3.5oz) macadamia nuts
Knead together flour, sugar and butter, then add eggs, vanilla extract and finally, macadamia nuts (better if you use knife to avoid them crumble).
Form a ball and wrap it in a polythene bag, place in the fridge for at least 1 hour.
After this time, take the the pastry and, on a floured surface, roll it out with a rolling pin at half centimeter (¼ inch) thick, and cut out biscuits with your favourite cutter.
I used a round one with a diameter of 5cm (2 inch) to make 18 biscuits.
Place them on a baking sheet coverded with parchment paper and bake at 160° (310°F) for 20 minutes.
Cool down a wire rack.