Soak cashews, uncovered, in hot water for 30 minutes. Don’t soak for too long as this will make the cashews too soft.
Drain and rinse the cashews with cold water.
Combine all ingredients in a blender and blend for 30 seconds.
Double strain the liquid through a strainer and a nut milk bag/multiple layers of cheesecloth/a kitchen cloth into a large bowl or pitcher. Make sure to squeeze the cloth to extract the oat milk while leaving the pulp behind.
Store inside an airtight container and keep refrigerated; the milk should last about 5 days.
