1️⃣ Preheat & Prep – Preheat oven to 160°C (320°F). Grease and line an 8×8-inch (20×20 cm) baking pan with parchment paper.
2️⃣ Mix Dry Ingredients – In a bowl, sift together cake flour, cocoa powder, baking soda, and salt. Set aside.
3️⃣ Whip the Egg Whites – In a large bowl, beat egg whites until soft peaks form. Gradually add 100g sugar, beating until stiff peaks form. Set aside.
4️⃣ Prepare the Wet Ingredients – In another bowl, whisk egg yolks and 50g sugar until pale and thick. Mix in vegetable oil, milk, and vanilla extract.
5️⃣ Combine Wet & Dry – Gently fold the dry ingredients into the egg yolk mixture until just combined.
6️⃣ Incorporate Egg Whites – Fold one-third of the whipped egg whites into the batter to lighten it. Then gently fold in the remaining egg whites until fully combined.
7️⃣ Bake –
