Pre-heat the oven to a temperature of 350°F.
Grease a 9-inch baking pan with vegetable oil so that the cake does not stick at the bottom during baking.
Since there are no mixing bowls involved in making this cake, add all the dry ingredients in the baking pan itself. Add the flour, sugar, cocoa powder and salt in the pan and stir all the ingredients with a fork until they are completely dissolved.
Now scoop three holes at the top in the mixture and add white vinegar, vanilla extract and vegetable oil respectively in them. This is a unique feature of the Wacky Cake which is not used in the making of any other delicacy.
Now pour the cup of water over the mixture and repeatedly stir the mixture until everything is well combined. Make sure you clean the edges as that could give the cake a rough look after it is baked.
Put the filling in the pre-heated oven and bake it for a good 30-40 minutes. To check whether the cake is done or not, insert a knife or a toothpick in the centre and if it comes out clean, the Wacky Cake is done.
Cool the cake for at least 5 minutes after taking it out from the oven. Serve when still warm for best results.