Once the water is boiling, add in the potatoes, carrots, onion and cashews. Boil until the potatoes and carrots are soft. About 15 minutes.
In a high speed blender, drain and add in the boiled potatoes, carrots, onions and cashews. Don't throw out the water you boiled the veggies in because you can use to thin sauce if needed.
Throw in the remaining ingredients and blend until smooth. Enjoy on top of veggies, over potatoes or use as a dipping sauce for chips.