How to bake cake in pressure cooker instead of microwave?
You should pre-heat the cooker for 10 to 15 minutes and not use the rubber of cooker while baking the cake. Place your cake on some sort of steel ring or on another pot so it will not be directly heat from bottom and bake your cake on low flame for 20 to 25 minutes.It will perfectly baked.

I also bake the cake using cooker for several time and it's perfectly baked.