Ensure all cold ingredients (butter, eggs, buttermilk) are at room temperature for proper emulsification and cake texture. For the ermine frosting, it is crucial that the cooked milk and flour mixture is *completely* cooled to room temperature before creaming with the butter, otherwise the frosting will curdle or melt. Avoid overmixing the cake batter after adding the dry and wet ingredients to prevent tough cakes. For a deeper red color, consider using a high-quality gel food coloring instead of liquid. Allow cakes to cool fully on a rack before frosting to prevent the frosting from melting.