1. Optional: If you’d like to toast the oats, set the 6-quart Instant Pot to “Sauté.” Place the butter in the pot. When the butter has melted, add the oats and cook, stirring often, for about 5 minutes, until fragrant. Press “Cancel.”
2. Add water or milk, salt, brown sugar, and cinnamon to the pot and stir. Make sure all the oats are submerged in the liquid.
3. Lock and seal the lid. Cook at high pressure for 12 minutes. Allow the pressure to release naturally for 10 minutes, then quick release the remaining pressure. When you open the pot, you’ll notice there is excess liquid. Give it a stir to incorporate. (Freezing instructions begin here.)
4. Stir in additional milk to reach the desired consistency. Serve with your favorite toppings (see ideas in the article above).

Freeze for Later: Follow steps 1 through 3. Let the oatmeal cool, then divide it evenly among two 6-cup greased jumbo muffin tins (or 12 jumbo silicone muffin liners) to create single-serving portions. Freeze until frozen solid, then pop out the oatmeal portions and transfer them to a gallon-size freezer bag or container. Seal and freeze.

Prepare from Frozen:  Place a serving of frozen oatmeal in a microwave-safe bowl. Add about 1/3 cup milk and microwave in 30-second intervals, stirring between each, until warmed through. Follow step 4.