Preheat the oven to 180 degrees C. Grease and flour a rectangular pan.
Whisk together the flour, baking powder, powdered sugar, chocolate milk, vegetable oil, eggs and instant coffee on low speed until the dry ingredients are moistened. Increase the speed to medium and continue beating another 2 minutes, pour the mixture into the pan.
Bake the cake in the preheated oven for 35 minutes. Check if the cake is cooked by inserting a toothpick in the center. If it comes out clean, it is ready. Remove from the oven and cool on a rack until it is no longer hot to the touch.
While the cake is still warm, prick it with a toothpick and make a bunch of small holes. In a bowl, beat the condensed milk, evaporated milk, and cocoa powder until the cocoa is incorporated into the liquid. Slowly pour the milk mixture evenly onto the cake.
Decorate with the whipped cream and a little cocoa powder.!!!