Yield: 3 square box cake bases
Egg yolk batter: – Egg yolks: 4 – Corn oil: 45g – Milk: 108g – Cornstarch: 20g – Low-gluten flour: 100g – Purple sweet potato powder: 9g Meringue: – Egg whites: 4 – Lemon juice or white vinegar: a few drops – Sugar: 75g Filling: – Whipping cream: 300g – Sugar: 16g – Blueberry jam: 65g Accessories and decoration: – Yellow peach: as needed – Whipping cream: as needed – Chocolate crisp pearls: as needed Separate the egg whites and yolks into oil-free and water-free containers. Refrigerate the egg whites temporarily. Place milk and corn oil in a mixing bowl, stir until emulsified. Sift in low-gluten flour, cornstarch, and purple sweet potato powder. Mix in a Z-shape until no dry powder particles remain, then add egg yolks. Mix with the same technique until the state shown in the figure appears: patterns form and slowly disappear. If too dry, add milk in small amounts multiple times; if too wet, add low-gluten flour in small amounts multiple times. Take out the egg whites, add a few drops of lemon juice or white vinegar, and whisk until fish bubble state appears. Add 1/3 of the sugar. Continue whisking until patterns just appear and disappear immediately, add another 1/3 of the sugar. Preheat the oven. Continue whisking until distinct patterns appear, add the remaining 1/3 of the sugar. Whisk until a soft peak state is achieved. Take 1/3 of the meringue and mix with the egg yolk batter using a cutting and folding technique. Pour the mixture into the remaining meringue, mix with the same technique, working quickly to prevent the meringue from defoaming. The finished cake batter. Pour the batter from 30cm height into a 28*28cm square pan, spread evenly, and tap a few times to remove bubbles. Bake in the oven at 135°C top heat/145°C bottom heat, middle layer for about 30 minutes, cover with tin foil in time. Take out the baked cake base and let it cool. Slice according to the box size. Whip the cream and sugar to 70% stiffness, add jam and continue whipping to 90-100% stiffness, suitable for piping. Transfer to a piping bag. Layer cake, cream, fruit, and chocolate crisp pearls, stack three layers.
