
In a large bowl, season the chicken pieces with salt and pepper.
In a large Dutch oven or pot, cook the bacon over medium heat until crisp. Remove the bacon and set aside, reserving the bacon fat in the pot.
Dredge the chicken pieces in flour, shaking off any excess. Brown the chicken in the bacon fat over medium-high heat, working in batches if necessary to avoid overcrowding the pot. Remove the chicken and set aside.
Add the onions, carrots, and celery to the pot and cook until softened, about 5-7 minutes. Add the garlic and cook for another minute until fragrant.
Pour in the red wine and bring to a simmer, scraping up any browned bits from the bottom of the pot. Add the chicken broth, thyme, and bay leaf. Return the chicken and bacon to the pot.
Bring to a simmer, then reduce the heat to low, cover, and simmer for 1 1/2 to 2 hours, or until the chicken is tender.
Add the mushrooms to the pot and cook for another 15 minutes, or until softened. Remove the bay leaf and thyme sprigs before serving. Garnish with fresh parsley, if desired.