Finely dice the onion, slice the carrot and mushrooms, and mince the garlic. To a heavy-base skillet, add 1 tbsp olive oil and place over medium-high heat. Add the mushrooms and cook for 3-4 minutes without stirring.
Add 1 minced garlic clove and stir. Cook for 3-4 more minutes until the mushrooms are browned. Transfer the mushrooms to a plate.
Add 1 tbsp of olive oil and add the chicken skin side down. Season with salt and pepper and sear for 5 minutes. Flip, season, and sear for 5 more minutes.
Remove the chicken pieces and place them on a plate. Drop the heat to medium, and add the chopped onions and carrots. Saute for 3-5 minutes until soft.
Add the remaining minced garlic and cook for 30 seconds until fragrant. Add the wine, chicken stock, tomato paste, thyme, bay leaf, and pearl onions. Stir and bring to a simmer.
Return the chicken to the skillet, drop the heat to medium-low, cover with foil, and cook for 20-25 minutes on a low simmer until the chicken is cooked through. Add the mushrooms, stir, and cook for another 2 minutes. Taste and adjust seasoning if needed.
Take the skillet off the heat and let it cool slightly. Chop the parsley and sprinkle it on top. Serve immediately!