Line a baking sheet with parchment paper and spread the macadamia nuts out evenly on the baking sheet. Bake for 10-12 minutes, until roasted. Remove the baking sheet from the oven and allow the nuts to cool.
Transfer the roasted macadamia nuts to your food processor and add the remaining ingredients. Blend until smooth, scrapping down the sides of the food processor intermittently as needed.
Notes
It took about 7-8 minutes of blending to get smooth macadamia butter using the food processor that I have.
You can easily omit the maple syrup if you are avoiding sugars.
Nutritional values are an estimate and will vary depending on the ingredients you use.