In a 16 oz. mason jar, add the oats, your plant-based milk of choice, and the pure vanilla extract. Stir to combine, and then place the blueberries on top. Put the lid on tightly and store in the fridge overnight.
In the morning, stir it again, and add in the pure maple syrup and extra plant-based milk if needed.
*These can be made 3-5 days in advance and stored in the fridge for that long.