Chuẩn bị kem bơ và để sang một bên. Phủ một lớp kem bơ mỏng lên bánh bằng dao pallet. Cho bánh vào tủ lạnh khoảng 30 phút. Làm sạch một mặt phẳng rộng và phủ đường bột lên. Để fondant ở nhiệt độ phòng.

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Then measure the top and sides of your cake with a piece of string. Lay a long piece of string over the top of the cake and fold the ends down against the sides of the cake. Trim of any excess string that touches the plate. Take the string off and set it aside. You will be using it to measure the size of your fondant.  If you are doing a multi-tiered cake, measure one tier at a time. For any other cake, measure the greatest width across the top (this would be diagonal from corner to corner on a square or rectangle cake) and then add twice the height. The buttercream will help the fondant stick to the cake, so make sure to get the top and sides of the cake. Try to get the surface as smooth as possible, as any bumps will show. If there are any cracks or holes in the cake, be sure to fill them in using buttercream and then smoothing it down.  Consider using a cake decorating turntable to make this step easier and quicker. You can also use light or dark ganache or apricot jam instead of buttercream. This will give the buttercream enough time to harden. If the buttercream is too soft, the fondant will slide right off. The surface must be smooth, as any imperfections will get imprinted in the fondant. Lightly dusting the surface with powdered sugar will prevent the fondant from sticking to your work surface. If it is humid where you live, use a mixture of one part cornstarch and one part powdered sugar. If it is very dry, then consider using a thin layer of vegetable shortening. This will make it easier to work with. You can knead it for about five minutes to make it softer and easier to work with; do not let it get too soft and sticky, however. Consider kneading in some gel or paste icing color. You can also add in some flavoring as well. Do not use a liquid food coloring.