Add the water, oats, maple syrup (if using) and salt to a high-speed blender and blend briefly, about 20 to 30 seconds, until the mixture looks creamy. Do NOT over-blend, as this will make the consistency more slimy.
Pour the blended mixture through a fine-mesh strainer, and tap the sides of the strainer to make sure the liquid strains through. (Don't use a spoon to press the pulp into the sides of the strainer, or the resulting milk will be slimy. This is also why you also don't want to use a nut milk bag for straining.)
For an extra-smooth milk, rinse off the strainer and then pour the milk through it a second time. This will strain out any extra debris for an super-smooth milk.
Use the milk right away, or store it in an airtight container in the fridge for up to 4 days.
Nutrition information is for roughly a 3/4 cup serving. This information is just an estimate and not a guarantee.Oat milk is best served cold, as it will thicken up when heated. Separation is normal when you store oat milk. You can shake it to reincorporate the settled sediment, or just pour from the top for a super-smooth milk.