Into a high-speed blender
(I use VitaMix), pour in the coconut milk including the beans and pod, drained cashews, water, brown sugar, and sea salt. Blend on medium-high speed for 30 seconds. Scrape down container. Blend again until silky smooth, about 30 seconds. It will get steamy - this is okay. Pour base mixture into a lidded container and store in refrigerator for at least 8 hours.