1Mix eggs, salt and 1 carton of sour cream together. Add enough flour to make a thick, semi-sticky dough.
Fill a kettle with water (this depends on how much soup you are making, but use a good size kettle). Add potatoes and carrots, simmer until 3/4 done.
While these are boiling (or a very strong simmer), simmer 1 - 2 TBSP butter in a small pan and add diced carrots and celery, heat till tender. Add this to potatoes.
While this is at a strong simmer, add knoephla by making "small dumplings" using a teaspoon and cutting into the knoephla dough as big as you want the knoephla to be. (the bigger the size or "dumpling", the longer they will need to cook) The knoephla will double in size, you may want to test a few samples to see what size you want. The knoephla is done when they rise to the top.
Take off the burner and add the 2nd carton of sour cream. Enjoy.