Grease the mold/baking dish (diameter of about 6”) with butter and line it with baking paper (bottom and edges). Pour the dough into the mold and smooth out the top. Place the mold in a bigger baking dish (with a higher edge) filled with hot water. Place in a preheated oven and bake at 340 ° F. After 15 minutes, turn the oven down to 320 ° F and after another 15 minutes, turn it off. Do not open the oven and leave the cake in for another 15 minutes. Then take it out and let cool. Once the cake cools down, remove from the mold and lightly dust with powdered sugar.