Step 1

FOR THE BROTH: Place chicken breast side down on cutting board. Using kitchen shears, cut through bones on either side of backbone. Reserve backbone. Using sharp chef's knife, cut straight down through breastbone to make 2 halves. Working with 1 half at a time, separate leg quarter and wing from each breast.

Step 2

Transfer chicken parts, backbone, neck, and giblets to Dutch oven. Add 9 cups water, onion, carrots, celery, and salt and bring to boil over high heat. Reduce heat to maintain gentle simmer. Cook, skimming off any scum that rises to surface, until breasts register 160 to 165 degrees, 15 to 20 minutes.

Step 3

Transfer breasts to plate. Add dill, peppercorns, and cloves to Dutch oven. Cover and continue to simmer 1 hour longer (check broth occasionally and adjust heat as necessary to maintain gentle simmer). Transfer leg quarters to plate with breasts. Discard wings, backbone, neck, and giblets. Strain broth through fine-mesh strainer. (You should have about 8 cups broth; if not, add enough water to yield 8 cups.) Clean Dutch oven. Shred chicken, discarding bones. (Cooled broth can be refrigerated for 3 days or frozen for 3 months. Shredded chicken can be refrigerated for 3 days.)

Step 4

FOR THE MATZO BALLS: Whisk eggs and schmaltz together in medium bowl. Stir in seltzer. Using spatula or wooden spoon, stir in matzo meal; salt; and baking powder, if using. Cover and chill in refrigerator until mixture is very firm, about 45 minutes. Lightly grease large plate. Divide mixture into 14 portions (about 1 heaping tablespoon each) and place on prepared plate. With your wet hands, roll portions into smooth balls.

Step 5

Bring 2 quarts water and ½ teaspoon salt to simmer in large saucepan. When water comes to simmer, reduce heat to low. Add matzo balls (water may bubble vigorously), cover, and cook for 15 minutes.

Step 6

FOR THE SOUP: While matzo balls cook, add broth and carrot, parsnip, and celery, if using, to cleaned Dutch oven and bring to simmer over high heat. Adjust heat to maintain very gentle simmer (broth should maintain temperature between 175 and 190 degrees). Using slotted spoon, transfer matzo balls from water to broth. Cover and continue to cook until matzo balls are tender in center, 20 to 30 minutes for floaters or 45 minutes for sinkers.

Step 7

Add 2 cups shredded chicken, if using, and cook until warmed through, 3 to 5 minutes. Season with salt and pepper to taste. Portion soup into bowls and garnish each serving with dill. Serve.