Matzo Ball Soup

Name: Matzo Ball Soup
Cuisine: American
Ingredients: 1 chicken (about 3 pounds); 2 celery ribs, cut into 2-inch pieces; 1 medium carrot, cut into 1-inch pieces; 3 parsley sprigs; 3 eggs; ¼ cup plus 2 tablespoons seltzer or soda water; ¼ cup plus 2 tablespoons seltzer or soda water; 3 tablespoons chicken fat (skimmed from the chilled chicken stock or store-bought, called schmaltz); 3 tablespoons chicken fat (skimmed from the chilled chicken stock or store-bought, called schmaltz); ⅔ to ¾ cup matzo meal; Salt and freshly milled white pepper; Salt and freshly milled white pepper; ¼ cup minced fresh parsley, for serving