In a large pot, add the chicken, 1 quart of water, onion, celery, garlic and peppercorns. Stew the chicken until completely cooked. Remove chicken from the broth and cool. Remove skin and bones. Cut the chicken into bite sized chunks or shred. Remove 1 - 2 cups broth to use in dumplings; allow to cool.
To the remaining broth, add the rest of the water, salt, pepper, bouillon cubes and shredded/cubed chicken and heat to simmering.
To make dumplings: Mix together dry ingredients. Mix egg with one cup of broth and add slowly to the dry ingredients. Use as much broth as needed to make a stiff dough. Knead the dough on floured board, roll very thin. Cut into 1-inch squares with a pizza cutter. Drop in simmering broth; cover and cook 20 minutes. Enjoy.
If freezing, I will freeze the dumplings, still uncooked, separately from the soup. When time to reheat it, just bring dumplings back to room temperature, reheat the soup to boiling and drop in the dumplings. Very tasty!