Beat butter, sugar and salt on medium (speed 5) using a hand held mixer for 1 minute until smooth.

Add egg yolks and vanilla, beat for 1 minute or until smooth.

Add baking powder, rice flour and half the plain flour. Beat with mixer on medium speed until flour is incorporated.

Add remaining flour and beat with mixer until flour is incorporated. Add macadamia nuts and chocolate, then mix through with a wooden spoon (dough gets a bit too hard to use mixer).

Scrape mixture onto a work surface, press together and shape into a 22cm/9" log.

Roll up in baking paper or cling wrap, twist ends then refrigerate for 2 hours.

Preheat oven to 200°C/390°F (180°C fan).

Line 2 trays with baking paper.

Remove log from fridge, unwrap and slice into 1.75cm / 3/4" thick slices (12 - 13 cookies).

Place 6 on each tray, bake for 10 minutes.

Turn oven down to 170°C/340°F (150°C fan), switch the trays between shelves.

Bake 15 minutes, remove from oven and cool cookies on tray.

Cool fully before serving.