A sunset-themed cake can be used for a number of occasions, from a honeymoon send-off to Hawaii to a retirement party. The layering of colours present in a sunset can be tricky to replicate with frosting, so try bands of coloured fondant rolled together. Choose four to five colours for the fondant. It's helpful to look at pictures of sunsets to get an idea of which colours to use.
Make or purchase enough fondant to cover your cake. Commercial fondant usually has a chart on the side of the box to guide you. Frost your cake with a layer of buttercream for flavour and to help the fondant adhere.
Separate your fondant into five or six pieces, or more, depending on how many layers of colour you desire. Each piece should be progressively smaller, with the two largest pieces reserved for the very bottom of the cake (the outside colour of the sunset) and the top of the cake, where the sun will rest.
Knead colour into each piece of fondant. Use two colours per piece for a realistic, marbled effect. The largest piece could be dark pink and orange, the next-largest piece dark orange and light orange, the next-largest light orange and pink, and so on until you've worked in all the colours of the sunset. Colour the other large piece of fondant yellow or yellow-orange. Work the colour in enough so that there is no remaining white, but leave the colour slightly streaky to give depth to the layered effect.
Roll the yellow piece of fondant into a ball. Sprinkle a generous amount of icing sugar on your work surface, and place the yellow ball in the centre. Press to about one inch thickness with the palm of your hand. Roll the rest of the fondant pieces into thick ropes. Circle the yellow piece with the ropes, placing the colours in the order you prefer. When you are finished, the fondant will resemble a bullseye on your work surface.
Sprinkle your rolling pin with icing sugar. Roll the fondant out, pressing each layer into the surrounding layers as you flatten them. You want the pieces to blend together to create one sheet of fondant. If you are having trouble with the layers blending, overlap the edges before rolling together.
Lift the fondant carefully and drape it over your prepared cake. The yellow centre should cover the top, centre of the cake. Smooth the fondant around the cake.
Cut three to six palm tree shapes and one circle shape from sugar cookie dough and bake. Let cool. Frost the trees with green and brown icing, and frost the circle with yellow icing. Attach the circle to the centre top of the cake with buttercream tinted yellow. Attach the trees to the side of the cake. Pipe a decorative border around the bottom edge of the cake with buttercream tinted to match the bottom layer of the sunset.
Dark or bright colours can stain your hands, so wear food-grade gloves when kneading the colour paste into your fondant.