1. Boil chicken breasts in chicken broth (doubles the flavor). Add onion if you like, until cooked. Can be a little pink because it's gonna cook in the oven too! Be careful not to cook too much because it can dry out very easily. Cover and chill overnight.
2. Next day, take out, save broth. Cube, chop, shred the chicken, whatever you like. Preheat oven to the temp for your croissants. Now take croissants, roll out, and cut little squares out, place chicken inside and pinch closed. The dough will go a long way.
3. Now place on cookie sheet, brush them with a little butter, and bake till they get a good golden brown. Take out, place in casserole dish pour soup and broth mixture over dumplings. Bake at 350°F till it bubbles. Take out, let cool and serve.