Combine the oats, water, salt, and cinnamon in the instant pot. Stir, cover, and seal.
Set pressure to HIGH and cook for 4 minutes. When the cooking time is complete, allow the pressure to release naturally, for about 10 minutes, before manually releasing the remaining steam and opening the Instant Pot.
Stir well and divide into four portions. Cooked steel cut oats may be stored in the refrigerator for 3-4 days. Serve warm with the toppings of your choice.
Notes
Milk may be substituted for half of the water in this recipe. However, cooking with all water is my preference. I prefer to add a drizzle of cream or a pat of butter for richness when serving, as desired. Sweeten as desired, with honey, maple syrup. or brown sugar.