Add oats to a large bowl and cover with water. Allow to soak for 15 minutes.
Pour the soaked oats through a sieve and rinse repeatedly, at least three times.
Put the rinsed oats, optional vanilla, optional salt and optional maple syrup into a blender.
Cover with around 3 cups water then blend until it smooth, about 1 minute with a high-speed blender.
Pour through a strainer into a large pitcher. Discard the small pieces of oats left in the strainer. Repeat until the oat milk is smooth, about 2 more times.
Pour the oat milk into a container with a tight fitting lid, such as a Mason jar. Store in the refrigerator for up to a week. Shake well before use.
If you are planning to use your homemade oat milk in a variety of sweet and savory dishes, I recommend including the vanilla extract and maple syrup only at the time of use. Thinner Oat Milk:If you prefer your oat milk to have a thinner consistency, add up to another cup of water, making sure to blend well.