Bring the broth to a boil in a large pot on the stove.
Combine 2 cups of the flour with the salt and baking powder. Whisk well.
Using your fingers, combine the butter with the dry ingredients until well incorporated. Add the milk and stir until you have a sticky ball of dough.
Dust flour on your counter top and roll out the dough to 1/4" thick. Using a pastry wheel (or, a knife), cut long strips of dough. Cut the long strips into small squares.
Gently place the dumplings into the boiling broth along with the reserved flour. You may not need all of the reserved flour. Add it tablespoon by tablespoon while mixture is boiling to determine how thick you want your broth to be. We like a very thick, almost gravy-like broth so I add a lot of extra flour to ours.
Let dumplings cook in the boiling broth for about 8 minutes until done. Then, add the chopped chicken. Season to taste with salt and pepper and serve.