The amount of time to let a cake cool before icing can vary depending on the size and type of cake. As a general rule of thumb: 1. For single-layer cakes: Allow the cake to cool in the pan for about 10-15 minutes after removing it from the oven. Then, transfer it to a wire rack to cool completely before adding the icing. 2. For layer cakes: Let the cake layers cool in their pans for about 10 minutes after baking. Then, carefully remove them from the pans and place them on wire racks to cool completely. It's essential to make sure the cake layers are completely cooled before adding the icing to prevent the frosting from melting or sliding off the cake. 3. For larger cakes, bundt cakes, or specialty-shaped cakes: These cakes may require slightly longer cooling times due to their size and thickness. Follow the specific recipe's instructions for cooling time or use the toothpick test (insert a toothpick into the center of the cake—if it comes out clean, the cake is ready to be removed from the pan). In general, it's best to let the cake cool completely to room temperature before icing it. If the cake is too warm, the icing might melt or become runny, leading to an uneven and messy appearance. Patience is key to achieving a beautifully iced cake, so resist the temptation to rush the cooling process!