Pouring a freshly made batch of silky ganache over a cake gives you the professional look of a pastry chef's desserts without all of the years of practice. Ganache, a rich chocolate coating made from melted dark or milk chocolate and heavy cream, can glaze pastries and cakes or be drizzled on top of ice cream. When substituting for ganache, you need a glaze that offers the same versatility and silky texture as well as the chocolate flavor.
Buttercream provides a medium-to-thick consistency similar to ganache. Many cake decorators use buttercream instead of ganache to frost cakes before placing a layer of fondant on top. Buttercream offers more durability than ganache, especially in hot weather. For a silkier buttercream -- which can be made in chocolate or vanilla -- use a recipe with actual butter and cream, not one that calls for vegetable shortening and milk.
A glaze gives you a similar finish to ganache, but is quicker to make and apply, making this option ideal when you're in a hurry. A chocolate glaze is made by melting chocolate and then pouring the melted chocolate over a pastry while the chocolate is still hot. To keep the melted chocolate pourable and smooth, add a small amount of vegetable shortening or oil. This gives the chocolate a velvety texture, similar to that of ganache, and a shiny finish once it hardens.
Chocolate whipped cream offers a creamy, airy texture that can be used instead of ganache, but it doesn't have the same luxurious texture. Use whipped cream as a ganache alternative if you want the chocolate flavor without the dense richness of ganache. You can make chocolate whipped cream with powdered sugar, heavy whipping cream and cocoa powder. Be sure to refrigerate any desserts covered with whipped cream.
Poured chocolate icing -- made from a combination of powdered sugar, cocoa powder and liquid -- can be used in place of ganache. A poured icing is suitable when you need a quick chocolate coating for your pastries, but you don't have time to make a ganache. Icing works as a suitable replacement for ganache when topping cakes or cupcakes but not if you intend to cover the surface with fondant. A poured icing dries hard, which means the fondant doesn't have a sticky surface to adhere to and can slide or buckle on the cake.
Some people avoid ganache because it contains dairy. If you’re looking for a ganache substitute because of the dairy, you can replace the heavy cream with almond, soy or coconut milk instead. These do change the flavor profile of your ganache slightly but still offer the same creamy texture. Flavor plain almond or soy milk with a touch of vanilla extract.