In addition to brushing the pan de muerto with butter and sprinkling with sugar, there are many different ways to decorate this festive bread. Try out sprinkling the loaves with colorful sanding sugars, vanilla sugar, sprinkles, or sesame seeds. You can also brush them with an egg wash before baking for a shinier finish. Or, with orange marmalade or orange simple syrup after baking instead of butter. To make orange simple syrup, simmer ½ cup of orange juice with ½ cup of sugar and a piece of peeled orange zest in a saucepan and simmer over medium heat, whisking as it simmers, or until the sugar is dissolved.