In the bowl of your 6-quart Instant Pot, stir together the water, almond milk, steel-cut oats, salt, and cinnamon. If desired, stir in the maple syrup or honey for sweetness.
Secure the lid and set the steam release valve to “sealing.” Select the “manual” or “pressure cook” function and set to high pressure for 4 minutes. The Instant Pot will take several minutes to come to pressure before cooking begins.
When the cook time completes, allow pressure to release naturally for 10 minutes (the display will show “L:10” or similar). Then, carefully move the valve to “venting” to release any remaining pressure before opening the lid.
Stir the oats thoroughly—they will be hot and may appear loose at first but will thicken as they cool.
Taste and adjust with extra cinnamon or sweetener if needed. Serve warm with your favorite toppings.