Ensure the cashews have been properly soaked and drained before starting. If using an ice cream maker, make sure the freezer base has been frozen for at least 7 to 24 hours prior to use—ideally, keeping it stored in the freezer ensures it’s always ready.
In a high-speed blender, combine the soaked cashews, coconut milk, vanilla bean paste, cane sugar, and sea salt. Blend on high for 2 to 4 minutes, or until the mixture is completely smooth and creamy. Depending on your blender, you may need to blend longer to ensure all the cashews are fully incorporated, creating a silky texture.
Transfer the blended mixture into a bowl or container and cover it. Blending can sometimes generate heat, so for the best results, refrigerate the mixture in the coldest part of the fridge for at least 4 hours, or up to 2 days if making the ice cream later.
Once the mixture is thoroughly chilled, remove it from the fridge. Set up the ice cream maker and insert the pre-frozen freezer base. Pour the ice cream mixture into the machine and churn according to the manufacturer's instructions, typically for 20 to 25 minutes. The ice cream should develop a thick, creamy consistency similar to soft serve. If not using an ice cream maker, alternative no-churn methods can be used.
Transfer the soft serve ice cream into a container, such as a loaf pan, and smooth the top. Press a piece of plastic wrap, reusable wrap, or parchment/wax paper directly onto the surface to prevent ice crystals from forming. Wrap the entire container securely and place it in the freezer for at least 4 hours, or overnight for a firmer texture. The ice cream can also be enjoyed immediately in its soft-serve state.
When ready to serve, remove the container from the freezer and let it sit at room temperature for about 5 minutes, just as you would with store-bought ice cream. Scoop and enjoy!