04Seal lid with vent closed and program instant pot to manual mode. Set pressure to low pressure. Then set to cook for about 45 minutes. 45 minutes will produce a crispy brown top. If you want something a little less crispy, you may want to try a few less minutes. (Update: Some people have reported an issue with their Instant Pot giving an overheating error or burn notice. It appears to be happening with certain models of the Instant Pot such as the 6-in-1 bluetooth version and some of the other newer IP versions. If this happens, you can also try to set it to "rice" mode, low pressure, 45 minutes. If your IP version doesn't allow you to adjust the time in rice mode, readers have reported success using "multigrain" mode and changing to low pressure.)
05Check on the cake when the Instant Pot indicates it's done cooking. Your instant pot should not have sealed because of the low pressure and lack of liquid. The cake will look quite pale when finished because this is the bottom of your cake. When you touch the cake, it should bounce back with no uncooked batter remaining on it and the cake should be pulling away from the sides. If you cake is not quite done, let it continue to cook on low pressure for a few more minutes.
06Use a spatula to further loosen cake from the sides of the pan. Sometimes the cake gets a little bit stuck to the bottom, so you just need to carefully peel it away with your spatula. Very carefully, pop the cake out upside down so that the bottom is now the top. The top of the cake should be a golden brown and crispy.