Finding cashew butter free of allergens became difficult, so we started making our own. We will never go back to store bought. This is easy, quick and the only additives are the ones you put in.
3 cups of Cashews, with nothing added, we use the large jar from a box store
2 Tablespoons of Swerve, Sugar or nothing at all
2 Tablespoons of Olive Oil
We make this in our Vitamix Blender. Put all the ingredients in the blender. Start at lowest speed but quickly move up to highest speed. While it is blending, use the tamper to press ingredients toward the blades.
At first, it will make a loud noise, but as it turns into cashew butter, the noise will change from high to very low. You will also notice that all the nuts have been mixed, and you are done.
It will take around 2 minutes or less, and you will have about two cups of cashew butter.
It will be warm when it is first done, but will cool quickly. Store in clean jar with a lid. 
