1. Prepare materials.
2. Pour the corn oil into a clean bowl without water, microwave for 1 minute, about 80 degrees.
3. Sift in low-gluten flour.
4. Stir until there is no dry powder, add the yogurt and stir evenly in a zigzag pattern.
5. Add 3 egg yolks.
6. The stirred batter is set aside.
7. Put the egg whites in a water-free and oil-free bowl and beat with an electric whisk.
8. Add a few drops of lemon juice, add white sugar in two portions and continue to beat.
9. Pass until the whisk has a strong small corner.
10. Take one third of the egg white and put it in the egg yolk batter, and mix it up and down with a silicone spatula.
11. Pour the mixed egg yolk paste back into the egg white bowl.
12. Still mix up and down evenly.
13. Pour the cake batter into the mold and shake it a few times.
14. Save a small spoonful of batter, add a little cocoa powder, and put it in a piping bag.
15. Extrude the stripes one by one.
16. Use a clean bamboo stick to gently draw lines in one direction.
17. Put the finished cake in a deep baking pan larger than the mold, and pour about 3 to 4 cm of water. Put it in a preheated oven and bake it in a water bath at 150°C for about 60 minutes. The temperature is for reference only.
18. Finished product.
