Cover the Instant Pot with the lid. Set the vent to sealing. Select the Porridge mode and cook on high for 3 minutes. If your Instant Pot doesn't have the porridge mode, pressure cook on high instead for the same amount of time.
When the cooking cycle is complete, wait for 10 minutes before releasing pressure.
Stir the oatmeal. Add peanut butter, vanilla essence, and honey. Mix well.
[optional step] To make chocolate peanut butter oatmeal, add cocoa powder and mix well.
Top it with chopped banana and drizzle it with more peanut butter. Serve warm.
Notes
When you use 3 cups of liquid while cooking oats in the Instant Pot, it may seem like a lot of liquid, especially for rolled oats, but it is needed, and here's why -
This will ensure that your oatmeal will not burn.
As the oatmeal cools down, it will absorb all the liquid making it creamy. If you use less liquid, you'll notice that the oatmeal is dried out and clumpy by the time you are ready to eat.
Pot in Pot Oatmeal
Pour 1 cup water into the inner pot. Place a trivet over it.
Place a stainless steel bowl over the trivet. Add milk, water, salt, and oatmeal to it. Mix well.
Cover the Instant Pot with the lid. Set the vent to sealing. Select the Porridge mode and cook on high for 10 minutes. If your Instant Pot doesn't have the porridge mode, pressure cook on high instead for the same amount of time.
When the cooking cycle is complete, wait for at least 10 minutes before releasing pressure.
Remove the bowl carefully using tongs
Stir the oatmeal. Add peanut butter, vanilla essence, and honey. Mix well.