Preheat the oven at 350 degree.
Sift the flour, sugar, cocoa powder and baking powder.
Mix the dry ingredients together, add warm coffee, oil, vinegar and vanilla extract. Whisk all the ingredient well.
Grease the baking tray with oil. Dust it with a little flour.
Pour the batter into the baking tray. Place the baking tray in an oven. If it is a thick cake bake it for 25-30 mins, if not then it needs only 15-20 min
Once baked, turn off the oven, let the cake rest in the oven for 5 mins.
Cool the cake for 30 min
Dust the cake with powdered sugar, slice and serve.