2Spread 1 cup (5 oz) of the pistachios and the macadamias on a baking sheet. Bake for 5-6 minutes until lightly toasted. Set aside for 15 minutes to cool.
3Put the remaining ½ cup (2 ½ oz) pistachios in the blender and secure the lid. CHOP for 5 seconds until coarsely chopped. Transfer to a medium bowl.
4Put the toasted nuts, oil and salt in the blender and secure the lid. MIX for 15 seconds. Scrape down the sides then CHOP for 20-30 seconds, stopping and using the tamper to press the ingredients into the blades.
5BLEND for 15 seconds then PUREE for a further 15 seconds, scraping down the side as needed.
6Remove the lid and scrape down the side of the blender. MILL for 30 seconds until well blended. Add to the bowl of chopped pistachios, mix well. Taste, adjust the salt to your liking. If the nut butter is too thick, add a little more oil and continue blending until a thick, spreadable consistency is reached.
7Spoon into a clean sterilized jar and store in the refrigerator for up to 1 month.