12 fresh duck legs (7 to 11 lb depending on amount of fat on legs)
2 lb shallots, peeled and, if very large, halved
4 lb parsnips, peeled and cut diagonally into 1-inch-thick slices (halve large slices lengthwise)
2 tablespoons minced garlic
1 1/2 tablespoons chopped fresh thyme or 1 teaspoon dried, crumbled
2 Turkish bay leaves or 1 halved California bay leaf
2 1/2 teaspoons salt
1 3/4 teaspoons black pepper
1/4 teaspoon ground allspice
2 cups dry white wine
6 to 8 cups chicken stock, homemade
or store-bought (preferably not canned broth; 48 to 64 fl oz)
Special equipment: 2 (13- by 9- by 2-inch) baking pans
Garnish: fresh thyme sprigs