Remove weight and filter from the lid of pressure cooker.
Place the pressure cooker on stove top, add 1 cup of salt, place some steel bowl or heat proof pot, cover and preheat on medium flame for 5 minutes. Then turn the flame on low.
In a bowl, sift together, flour, cocoa, salt, baking soda and baking powder. Mix to combine.
Heat ½ cup of water in microwave for 40 seconds, add coffee and stir to dissolve. Set this aside.
Into the dry ingredients, add yoghurt, milk, vanilla extract and hot coffee water. Beat on slow speed for 1 minute or until everything is well combined.
Pour this mixture into a greased and lined pan. Tap to remove air bubbles.
Carefully place this batter into pressure cooker.
Cover and bake on medium flame for 5 minutes.
Then bake for 35-40 minutes on low flame.
After 35 minutes insert toothpick if comes out clean cake is done. If it is not done bake 5_10 min more.
After 5 minutes, remove the cake from the pressure cooker, and let it stand for about 10 minutes to cool.
Chocolate frosting: Pour milk to a pot or pan.
Add cocoa and sugar. Mix well and boil stirring often.
Within few minutes the mixture turns thick. Add vanilla extract and turn off the heat.
Cool this completely. The chocolate sauce thickens after cooling.
Now beat the cream with electric beater 2 min .
Now frost the cake with chocolate frosting and enjoy!