Boil the cashews and potatoes in a saucepan until potatoes are fork tender, 5-10 minutes. Drain and rinse well.
Pour the milk into the saucepan. Bring to a low boil.
Place all of the ingredients, including the boiling milk, cooked potatoes and cashews into a high-speed blender and blend on high speed for 1-2 minutes, until very smooth.
Immediately pour into a glass or plastic bowl, mold, or container; and allow to chill in the refrigerator for at least 3 hours.
Once the mozzarella is firm, you can slice or shred and use in any recipe that calls for it, though the flavor improves with time and is best the next day.
Store in a covered container or wrapped in plastic wrap in the refrigerator for up to 5 days.
Notes
* Kappa Carrageenan is necessary for shreddable and sliceable cheese. If you omit it, the mozzarella cheese will remain in a soft sauce state. It’s still delicious but will need to be spooned or poured onto your pizza or lasagna. You may also substitute with 3 Tbsp agar agar, if desired, but it may result in a softer less melty cheese.