Combine all dry ingredients, whisking well to work out any clumps in the cocoa powder.
Add in the wet ingredients and stir with a wooden spoon until well combined. The batter will be on the thicker side.
Oil a 6-inch cake pan.
Pour the batter into the cake pan.
Place a trivet in your Instant Pot insert and add 2 cups water.
Place the cake pan on the trivet.
Close the lid and the vent.
Press the Manual button and adjust the timer to 12 minutes. Allow a 10-minute natural release after baking time is done. Release any remaining steam by opening the vent.TIP: Hold the lid straight (horizontal) instead of tipping to avoid water on the lid dripping on your cake.
Lift the cake pan out and allow it to cool on a cooling rack.
Run a spatula or plastic knife around the edge of the cake to release it from the pan and turn the cake out onto a platter or cooling rack.
Slice and decorate as desired.
Strawberry fruit spread (no sugar added) is really exceptional on this cake.
Cut and serve!
Video
Notes
Please note that the nutrition data below is a ballpark figure. Exact data is not possible.