Drain and rinse the soaked cashews, then add everything to a blender or food processor and whizz until smooth. If you have a high speed blender this will take 10-20 seconds. You can still achieve a smooth sauce with a food processor, you'll just need to spend a few more minutes on it and stop and scrape down the sides a few times.
Taste and adjust seasoning.
The sauce will thicken a bit on standing, and will keep refrigerated for a few days if you don't scoff it all immediately.
Serve with mixed roast vegetables and brown rice or quinoa for a satisfying and healthy meal.
Notes
Preparation time doesn't include soaking time for the nuts.