Place chicken in a large pot and almost cover with water. Add onion half, salt and pepper and garlic powder. Bring to boil, reduce heat to simmer and cook, covered for 50 minutes, or until chicken tests done. Remove from heat and pull chicken from pot. When cool enough to handle, remove skin and discard. Remove meat and pull into serving pieces. Discard chicken bones and onion from pot. Skim fat from the top of stock. Return chicken pieces to the pot of stock. Meanwhile, in a medium mixing bowl, combine flour, baking powder and salt. Cut in shortening, and enough milk so that batter is smooth but not too runny. Bring pot of chicken and stock to a simmer, then drop batter by spoonfuls into the hot liquid. Let cook 5 minutes, uncovered, then cover the pot and cook another 5-7 minutes, or until dumplings test done. Serve broth, chicken and dumplings in soup bowls and season to taste. 397.3 calories, 16.3 g fat, 38.5 g protein, 21.6 g carbohydrate, 114 mg cholesterol, 375 mg sodium.