Instant Pot carrot cake is just the beginning when learning how to bake a cake in a pressure cooker. The possibilities are endless once you learn this!
Prepare carrot cake as directed on the box. Spray the inside of your 7" bundt pan with non stick spray.
Pour 1.5 c water into your pressure cooker and lower down a trivet.
Fill bundt pan with batter minus 1/2 cup of batter (I tend to leave out 1/2 c of batter so it doesn't rise quite as much but others have noted that it will in fact fit the whole box of prepared mix).
Cover pan with foil. Make a sling out of foil to lower down bundt pan, or use a trivet with handles so you can lift it back out.
Close your lid and steam valve and set to pressure high for 28 minutes.
Allow steam to naturally release completely. Remove bundt pan and immediately take off foil.
Put on cooling rack and allow to cool until edges pull away from sides a bit.
Put a plate on top and gently flip the pan upside down so cake slides out. Drizzle melted cream cheese frosting on top and serve.