Preheat the oven to 325°. Heat 1 tablespoon of the olive oil in a large enameled cast-iron casserole. Add 2 of the turkey drumsticks to the casserole, season with salt and pepper and cook over moderately high heat until browned all over, about 8 minutes; transfer to a plate. Reduce the heat to moderate and repeat with the remaining 2 drumsticks and salt and pepper. Discard the fat.
Add the wine to the casserole and cook, scraping up the browned bits on the bottom, until it has reduced to 1/2 cup, about 10 minutes. Tie the thyme and rosemary into a bundle and add to the casserole along with the drumsticks and stock and bring to a simmer. Cover and braise in the oven for 1 1/2 hours, turning the drumsticks occasionally.
Meanwhile, in a small bowl, soak the prunes in the brandy until plump, about 30 minutes. Bring a small saucepan of water to a boil. Add the pearl onions and blanch for 2 minutes, then drain and let cool slightly. Trim the root ends of the onions and slip off the skins. Heat the remaining 1 teaspoon of olive oil in a small skillet. Add the pearl onions and cook over moderately high heat until lightly browned, about 5 minutes.
Add the onions, prunes and any remaining brandy to the casserole. Cover and braise for 1 hour longer, or until the turkey drumsticks are tender.
Using a slotted spoon, transfer the turkey, prunes and pearl onions to a platter. Discard the herb bundle. Skim the fat off the cooking liquid, then simmer the liquid over moderate heat until reduced to 1 1/2 cups, about 30 minutes. Return the turkey, prunes and onions to the casserole, simmer until hot and serve. Discard the turkey skin before eating.
Make Ahead: The stew can be refrigerated for up to 3 days.
Serve With: Boiled noodles, steamed rice or boiled potatoes.
Wine Recommendation: A berry-flavored Zinfandel has the right amount of fruitiness and sweetness to complement the rich fruit-based sauce here. Pick a lighter example that won't overwhelm the turkey, such as the 2000 Quivira Dry Creek Valley or the 2000 Foppiano Dry Creek Valley.
Notes: One Serving: 503 calories, 0 gm total fat, 1 gm saturated fat, 34 gm carb.