When the cake turns golden brown in color, take it out of the oven and conduct the toothpick test to check whether it is done fully. While the cake is being baked, you can prepare the icing for it. To make the frosting, take milk in a small bowl and combine it with powdered sugar, vanilla and butter. Beat the mixture at medium speed till it becomes smooth and fluffy. When the cake is fully done, apply the frosting over it and decorate it as you desire.