Preheat the oven to 325 F.
In a large Dutch oven, cook the bacon over medium-high heat until crisp and golden brown, about 8 minutes. Using a slotted spoon, transfer the bacon to a paper towel lined plate and set aside.
Season the chicken with 1 tablespoon of the salt and 2 teaspoons of the white pepper. Add 1/2 cup of the flour to a resealable 1 gallon plastic food storage bag.. Place the chicken in the bag a few pieces at a time and shake until well-coated with the flour. Remove the chicken from the bag and, working in batches, brown the chicken pieces in the rendered bacon fat over medium-high heat until golden on all sides, 3 to 4 minutes per side. Once browned, transfer the chicken to a platter and set aside. Repeat with the remaining chicken.
Pour off and discard and remaining fat and dark bits left in the pan and return to the stove. Add the butter and heat over medium heat. When it begins to bubble, add the fennel, leek, parsnip, celery, and garlic and cook until the vegetables are tender, 6 to 8 minutes. Stir in the remaining 3 tablespoons flour until; combined and cook for 2 minutes. Add 1 cup of the wine and cook, stirring and scraping up any browned bits from the bottom of the pan, until the liquid is almost evaporated.
Add the grapes, stock, thyme, bay leaf, and remaining wine, 1 teaspoon of salt, and 1/2 teaspoon white pepper and bring to a brisk simmer. Add the bacon and the browned chicken back to the pan, cover and place the pan in the oven. Cook until the chicken is tender and the sauce has thickened, 2 to 2 1/2 hours.
Remove the thyme sprigs and bay leaf and discard, and then serve the dish directly from the Dutch oven over cooked egg noodles, rice or with warm French bread.