In a stockpot, add chicken broth, chicken breast and bring to boil over medium heat.
While waiting for breast to cook, bring another pot of water to boil, add some salt and follow box's instruction to cook pasta to past al dente.
Once pasta is done, strain off the liquid, do not rinse and set aside.
Have a small icy cold water bath ready to transfer the breast into once it is cooked.
Add corn kernels and pasta to hot broth. Peel and dice carrot and add to pot as well. Bring this stock back to boil then adjust heat to low/simmering.
Once chicken breast is cool off to room temperature, shred with a fork then add back to stock pot.
Taste test and adjust seasoning with salt if need.
Mix starch/flour with 1/2 cup of water, stir well to combine, make sure no white residue on the bottom.
Pour that starch liquid into soup pot while stirring to fully mix and thicken the soup.
Crack egg over a sieve or slotted spoon into the soup. Stir to fully mix and adjust heat to keep warm while/until serving.
To serve: ladle soup into bowl, sprinkle some chopped celery and dash of freshly ground pepper. Enjoy while it hot.