Preparation: Preheat the oven to 170°C (340°F). Grease the cake mold with a layer of butter, ensuring all corners are covered. This will help prevent the cake from sticking and make it easier to remove after baking.

Whisk the Eggs: Crack 4 room-temperature eggs into a clean, dry bowl. Add 5 drops of white vinegar or lemon juice to eliminate any eggy odor. Mix in 60g of white sugar. Place the bowl over a water bath (around 40-50°C). Be careful not to let the water touch the bowl. The warm water helps the eggs beat more easily. Use an electric mixer to beat the eggs on low speed for 1 - 2 minutes until the mixture becomes lighter in color and slightly increases in volume. Then, switch to high speed and continue beating for 5 - 8 minutes until the mixture becomes thick and fluffy. The batter should form ribbons that hold their shape for a few seconds when the beaters are lifted.

Add Corn Oil and Sift in Flour: Pour 20g of corn oil into the whipped egg mixture. Sift 120g of low-gluten flour over the mixture. Gently fold the flour into the egg mixture with a spatula, lifting from the bottom and turning over, until it is well-combined. Be sure to work quickly and gently to preserve the fluffiness of the egg mixture.

Prepare the Mold: Carefully pour the batter into the prepared mold. Fill it about 90% full. Sprinkle a layer of white sesame seeds on top for decoration.

Shake to Remove Air Bubbles: Gently shake the mold on the countertop a few times to release any large air bubbles trapped in the batter. This helps ensure that the cake's texture is even and free of big holes.

Bake the Cake: Place the filled mold on the lower rack of the preheated oven. Bake at 170°C for 20 minutes. Don't open the oven door during baking to avoid a temperature drop, which may affect the cake's rise. You can tell the cake is done when the surface turns golden and it no longer rises.

Remove from the Mold: After 20 minutes, wear heat-resistant gloves and take the mold out of the oven. Let the cake cool for a few minutes on a wire rack. Once it's cool enough to handle, gently remove it from the mold. You now have a soft, fluffy Chinese egg cake ready to enjoy!