Place the chicken breast up in a dutch oven or large pot. Add water to cover the chicken. Add the celery, onion, garlic powder, thyme, black pepper, and poultry seasoning. Dissolve bouillon in boiling water and add it to the pot. Cover and bring to a boil (8 of 10). Reduce to a simmer (4 of 10). Simmer for 1 hour.
Remove chicken and allow to rest. Skim the fat off the top of the broth. A fat seperator is the easiest way. Set aside 1 1/2 cups of broth to cool.
When the chicken has cooled remove skin, bones and fat. Shred the meat and return it to the broth.
In a small bowl whisk the eggs and salt. Slowly whisk in 1/2 cup of the reserved broth and set-aside. Place the flour in a large bowl. Push the flour up the sides of the bowl to make a well. Pour the egg/broth mixture into the well. Fold the flour over the broth working around the bowl until the the dough is too thick to fold. using clean hands knead and roll the dough on the bowl until the broth is fully absorbed. Cover the bowl with a wet paper towel and allow the miosture to settle in the dough.
Bring the broth back up to a boil. Disolve the corn starch in 1 cup of cooled reserved broth. Slowly stir it into the broth.
Turn out the dough onto a floured work surface. cut the dough ball in half. Return half the dough to the bowl and cover with the wet towel. Roll the dough to a thickness of 1/8". You may need to lightly dust the dough and flip it to get it rolled out thin. Using a pizza cutter, cut the rolled dough into 1" square pieces.
Bring the broth up to a rouring boil and drop the dumplings in one at a time. the dumpling will sink to the bottom and float when cooked. Continue adding the dumplings one at a time until they are all in the broth.
Roll the other half of the dough ball. Cut the dumpings and add them to the pot. Simmer for 5 minutes. Serve.
