👉 The cake fluid, also known as cake batter or cake mixture, is the foundational component of a traditional sponge cake. It consists primarily of flour, sugar, eggs, and often cream of tartar or baking powder, which serve to bind the ingredients together and provide structure. The batter is typically mixed until it forms a smooth, lump-free consistency, ensuring that the cake rises properly during baking. The addition of liquid ingredients like milk or buttermilk further lightens the batter, contributing to the cake's tender crumb and delicate texture. The precise balance of ingredients in the cake fluid is crucial for achieving the desired light, airy, and moist characteristics of a classic sponge cake.