When glazing a cake with ganache, the correct order of icing is:

When glazing a cake with ganache, the recommended method is to apply the ganache to the sides first and then to the top. This approach helps ensure that the ganache drips down smoothly from the top to the sides, creating an even and professional-looking finish. By starting with the sides, you can more easily manage the flow of the ganache, allowing any excess to run down and coat the edges evenly before topping off the cake.

Looking at the other possible options, starting with the top could lead to uneven distribution if excess ganache runs down the sides unevenly. Having no specific order could work in some contexts, but it does not guarantee the same professional appearance and could lead to more mess and wasted ganache. Lastly, icing the bottom first is not practical, as it may not stay intact while the cake is being handled for topping, leading to potential damage to the final presentation. Therefore, the method of applying ganache to the sides first provides the best result for a smooth and appealing glaze.