Preheat the oven to 350F.
Cook the bacon pieces in a large Dutch oven over medium heat until crisp, about 8-10 minutes. Remove the bacon with a slotted spoon, leaving the fat in the pot.
Pat the chicken pieces dry with the paper towels and season with the salt and pepper.
Brown the chicken skin-side down in the bacon fat for 5-6 minutes per side until deeply golden. Transfer to a plate.
Add the pearl onions, carrots, and mushrooms to the pot. Cook for 8-10 minutes until softened and lightly browned.
Add the garlic and cook for 1 minute until fragrant.
Sprinkle the flour over the vegetables and cook for 2 minutes, stirring constantly.
Pour in the brandy and scrape up the browned bits from the bottom of the pot.
Add the red wine while stirring continuously.
Stir in the chicken broth, tomato paste, bay leaf, and thyme until combined. Return the bacon to the pot.
Place the chicken pieces skin-side up in the liquid. Bring to a simmer.
Transfer the covered pot to the oven and braise for 60-75 minutes until the chicken reaches 175F.
Remove the chicken to a serving platter. Remove the bay leaf and thyme sprigs.
If desired, simmer the sauce on the stovetop for 5-10 minutes to thicken.
Taste and adjust seasoning with salt and pepper.
Pour the sauce and vegetables over the chicken and garnish with the fresh parsley.