1.Preheat oven to 170°C (150°C fan forced). Grease square cake pan, line base and sides with baking paper, extending paper 5cm (2 inches) above sides. Grease two holes of the loaf pan and one hole of the texas muffin pan. Grease four holes of the standard muffin pan and nine holes of the mini muffin pan.
2.Make cakes according to directions on packets. Drop ¼ cup of the mixture into the greased holes of the loaf pan, drop ⅓ cup of the mixture into the greased hole of the texas muffin pan. Bake cakes about 25 minutes. Stand cakes in pans 5 minutes before turning, top-side up, onto wire rack to cool.
3.Drop 2½ level tablespoons of the mixture into the greased holes of the standard muffin pan. Bake cakes about 20 minutes. Drop 2 level teaspoons of the mixture into the greased holes of the mini muffin pan. Bake cakes about 15 minutes. Stand cakes in pans 5 minutes before turning, top-side up, onto wire rack to cool.
4.Spread remaining mixture into square pan. Bake about 50 minutes. Stand cake in pan 5 minutes before turning, top-side up, onto wire rack to cool.
5.To make butter cream. Beat the butter (and any flavouring if using) in a small bowl with an electric beater until the butter is as white as possible. (This will result in a whiter buttercream which will give you better results if colouring it). Gradually beat in half of the sifted icing sugar, then the milk, then the remaining sifted icing sugar.Beat until the butter cream is smooth and spreadable. Keep scraping down the side of the bowl during beating.
6.Level all cake tops. Secure square cake, cut-side down, on cake board with a little butter cream. Tint butter cream pale yellow, spread over top and sides of the large cake. Sprinkle all over with the coconut, pressing into sides of cake.
7.Spread small cakes, one at a time, all over with butter cream then roll to cover in the coconut.
8.Assemble sandcastle by positioning four standard muffins in centre of the square cake, top with loaf cakes then texas muffin.
9.Position mini muffins on top of the castle and around the edge of the square cake to make turrets.
10.Using picture as a guide, position the decorations on the castle, securing with a little butter cream when necessary.
EQUIPMENT: Deep 20cm (8-inch) square cake pan 8-hole (½-cup/125ml) mini loaf pan 6-hole (¾-cup/180ml) texas muffin pan 12-hole (⅓-cup/80ml) standard muffin pan 12-hole (1-tablespoon/20ml) mini muffin pan 30cm (12-inch) square cake board To toast the coconut, put it in a large frying pan, then stir it constantly over a medium heat until it is browned lightly and evenly. Immediately turn the coconut out of the pan and spreaditonto a largetrayto cool it as fast as possible. We made our own white chocolate seahorses and shells using 100g(3ounces) melted white chocolate Melts in chocolate moulds. However, you can readily buy marbled white and milk chocolate seahorses or shells.