Mix dry ingredients in a big bowl and whisk together.
Mix wet ingredients in another bowl.
Add the wet ingredients to the dry ingredients and beat until smooth. It will be quite thin, but do not overmix.
Pour into a silicone cake pan that fits in Instant Pot.
Place 500ml cold water into the inner pot. Cover the cake pan with foil and place inside the inner pot on top of the trivet.
Select Manual High Pressure and set the time for 60 minutes followed by 15minutes natural pressure release.
Allow the cake to cool completely in the cake pan before topping with fresh berries and serving.