Prepare a fresh sweet corn or purchase niblet from supermarket.
Chop the sweet corns with knife; keep 1/2 of the sweet corns in a small bowl.
Add the left sweet corn with around 2 tablespoons of clean water in a food processor and blend until they turn into chunks
Transfer the blended corn, and the whole sweet corn to a pot, and add water. Cook for 4 minutes after the water boils. Add rock sugar if using and a very small pinch of salt.
Mix cornstarch with around 2 tablespoons of water. Stir well to avoid any bumps. Add the water starch to the soup. Bring to boiling again until the soup base become thick in texture.
Now, slow down the fire and slowly stir the whisked egg liquid in. Stir the soup with a scoop slowly, gently, and continually. And in one direction. Serve hot.
Notes
If you have chicken stock, then water with chicken stock. Chicken breast can also be added if meat is desired.