Preparation Combine first 3 ingredients in heavy large pot and bring to boil. Reduce heat to medium, cover and simmer until parsnips are tender, about 5 minutes. Using slotted spoon, transfer parsnips to small bowl. Add potatoes and apples to same pot. Cover; simmer until very tender, about 20 minutes. Remove from heat. Using slotted spoon, transfer potatoes and apples to large bowl; add 3 tablespoons butter. Mash until almost smooth. Season with salt and pepper. Pour broth mixture from pot into medium bowl; reserve pot. Sprinkle chicken with salt, pepper and 4 teaspoons thyme; dust with flour. Melt remaining 2 tablespoons butter in reserved pot over medium-high heat. Add half of chicken. Sauté until brown and cooked through, turning with tongs, about 5 minutes. Using slotted spoon, transfer sautéed chicken to 11x7x2-inch glass baking dish. Repeat with remaining chicken. Top with parsnips, remaining 2 teaspoons thyme and peas. Return broth mixture to same pot; add brandy and whipping cream. Boil over medium-high heat until sauce is reduced to 1 1/4 cups, scraping up browned bits, about 3 minutes. Season with salt and pepper. Spoon over chicken. Cover with potato-apple mixture. (Can be prepared 1 day ahead. Refrigerate until cold, then cover and keep refrigerated.) Preheat oven to 350°F. Bake casserole uncovered until potato topping is crusty and chicken filling is heated through, about 35 minutes (about 45 minutes if refrigerated).
Preparation Combine first 3 ingredients in heavy large pot and bring to boil. Reduce heat to medium, cover and simmer until parsnips are tender, about 5 minutes. Using slotted spoon, transfer parsnips to small bowl. Add potatoes and apples to same pot. Cover; simmer until very tender, about 20 minutes. Remove from heat. Using slotted spoon, transfer potatoes and apples to large bowl; add 3 tablespoons butter. Mash until almost smooth. Season with salt and pepper. Pour broth mixture from pot into medium bowl; reserve pot. Sprinkle chicken with salt, pepper and 4 teaspoons thyme; dust with flour. Melt remaining 2 tablespoons butter in reserved pot over medium-high heat. Add half of chicken. Sauté until brown and cooked through, turning with tongs, about 5 minutes. Using slotted spoon, transfer sautéed chicken to 11x7x2-inch glass baking dish. Repeat with remaining chicken. Top with parsnips, remaining 2 teaspoons thyme and peas. Return broth mixture to same pot; add brandy and whipping cream. Boil over medium-high heat until sauce is reduced to 1 1/4 cups, scraping up browned bits, about 3 minutes. Season with salt and pepper. Spoon over chicken. Cover with potato-apple mixture. (Can be prepared 1 day ahead. Refrigerate until cold, then cover and keep refrigerated.) Preheat oven to 350°F. Bake casserole uncovered until potato topping is crusty and chicken filling is heated through, about 35 minutes (about 45 minutes if refrigerated).