Preheat oven to 350 degrees. Gather your ingredients so that you have everything close at hand on the counter or table.
Prepare the Ingredients
Place chicken thighs in a large bowl with the dry red wine, chicken stock, and brandy. Allow this to marinate for 12-15 minutes while you prepare the other ingredients.
Using a sharp knife and cutting board, slice 2-3 pieces of thick steak bacon, cut into 1/2" pieces.
Dice the sweet onion. Peel and slice carrots into 1" pieces. Slice celery into the same-sized pieces. Mince the garlic.
Brown the Bacon and Chicken
Add the sliced bacon pieces to a large Dutch oven and cook over medium-high heat until crispy, 6-8 minutes. When browned, remove the bacon and place on a plate or platter for later.
Remove the chicken thighs from the wine marinade and pat the chicken dry with paper towels. Sprinkle with kosher salt and freshly ground black pepper.Do not discard the wine marinade, as you'll be using it soon in this recipe!
Place the chicken in the Dutch oven, to cook in the bacon grease. Sear 6-7 minutes on both sides, until the skin is nicely golden brown. When browned, place the chicken thighs with the bacon.
Prepare the Stew
Add the diced onion, and sliced carrots and celery to the bacon grease and saute until the onion is tender, 8-10 minutes. Add the minced garlic and cook for an additional minute.
Create a hole in the center of the Dutch oven and add to it the tomato paste. Allow the paste to simmer until it becomes fragrant and darkens, stirring constantly.
Pour in the reserved wine marinade, and mix it in with the tomato paste and vegetables. Use a wooden spurtle to scrape the bottom of the pan to release the browned bits of chicken (or fond), which will give this dish even more flavor as it bakes.
Place the browned chicken and bacon into the stew, along with any juices on the plate. Add the fresh thyme to the top and bring the dish to a low boil.
Cover with a lid and transfer the Dutch oven to the preheated oven. Allow to bake for 20-30 minutes until the chicken is cooked through and no longer pink in the middle.
Finishing the Stew
To finish the stew, add extra virgin olive oil to a small skillet, along with a tablespoon of butter. Add the sliced mushrooms and onions to the oil and saute for 8-10 minutes over medium-high heat until browned and tender.
Next, prepare the Beurre Manie by mashing together the all-purpose flour and softened butter in a small bowl until combined.
Remove the Dutch oven from the oven and place it on the stovetop. Add the thickener to the stew and stir it into the sauce.
Add the sauted mushrooms and sliced onions to the stew, carefully stirring them into the sauce with the chicken pieces.
Return the Dutch oven (without the lid) to the oven and allow to cook for another 12-15 minutes, until the sauce has thickened.
Season with kosher salt and freshly ground black pepper.
To serve, place 1-2 pieces of chicken on each plate, along with mashed potatoes, and spoon vegetables and sauce over both. If desired, garnish with fresh thyme and parsley. Serves 4-6.
*Unless otherwise indicated, all butter used on this recipe site is salted.