This cake is a North American treat, a humble Aussie attempt. The best thing is the gorgeous color. Double the recipe for 4 layers (or 1.5 for 3). Originally, the red was subtle, from a reaction between acidic vinegar and buttermilk. For best color, use an acidic batter and Organic Unsweetened Cocoa, not Dutch Pressed Cocoa. Use Cake Flour rather than plain flour. Traditionally iced with French Roux Frosting, but cream cheese is great.
This cake is a North American treat, a humble Aussie attempt. The best thing is the gorgeous color. Double the recipe for 4 layers (or 1.5 for 3). Originally, the red was subtle, from a reaction between acidic vinegar and buttermilk. For best color, use an acidic batter and Organic Unsweetened Cocoa, not Dutch Pressed Cocoa. Use Cake Flour rather than plain flour. Traditionally iced with French Roux Frosting, but cream cheese is great.
Operating within strict limits on leavening timing requires having 20cm cake tins greased and floured before the batter touches the bowl. Historical versions of this confection relied exclusively on the chemical reaction between acidic buttermilk, vinegar, and natural anthocyanins in unalkalized cocoa powder to produce a reddish hue without heavy artificial dyes. Selecting non-alkalized organic unsweetened cocoa ensures that the natural acidity remains preserved, interacting properly with the added lemon juice and vinegar to build both the iconic pigmentation and a characteristic tight, dense crumb that behaves more like a mud cake than a delicate sponge. Creaming butter and sugar until the mixture turns pale yellow incorporates enough air to support the heavy flour without relying on excessive chemical agents.
Substitutions demand precision regarding chemical balance because Dutch-processed cocoa undergoes alkalinization that neutralizes the vital acids needed to trigger the baking soda reaction. Swapping standard all-purpose flour for finely milled cake flour reduces protein development, yielding a tender crumb that absorbs moisture evenly from the buttermilk and eggs. Whisking the food coloring and cocoa into a smooth paste prior to incorporating it prevents streaks and ensures even distribution throughout the batter without requiring over-mixing. Slow initial speeds on the electric mixer keep the crimson splatter contained within the mixing bowl while the fats emulsify with the dairy.
Timing dictates success during the final stages of mixing when the baking soda and white vinegar combine to create an immediate carbon dioxide fizz. Folding this foaming mixture into the batter rapidly and transferring the 20cm tins to a 175 degree Celsius oven—or 165 degrees for fan-forced appliances—captures those rising bubbles before they dissipate. Baking takes approximately 25 minutes, ending the moment a wooden skewer inserted into the center emerges completely clean. Allowing the layers to rest inside their pans for 10 minutes before transferring them to a wire rack prevents structural collapse while cooling.
Applying a thin crumb coat of cream cheese frosting traps stray red particles before the final layer goes on smoothly with a palette knife. Pairing a slice of this rich dessert with a bitter beverage like black coffee balances the intense sweetness of the sugar and cream cheese blend. Reserved cake trimmings crumbled over the top provide a rustic finish that masks minor surface irregularities without requiring complex piping skills. Keeping the assembled dessert chilled helps firm the roux-based or cream cheese butter mixture for clean slicing.