Season the chicken on all sides with salt and pepper.
Add the butter to a 12” large cast-iron skillet or Dutch oven over medium-high heat.
Add in the chicken skin side down and cook for 3-4 minutes per side or until well browned.
Remove the chicken and set aside. Next, add the onions and mushrooms to the pan and sauté over low heat for 5 minutes white frequently stirring.
Add in the garlic and cook for a further minute and deglaze with lemon juice.
Stir in the flour until completely mixed in and then add in the wine and stir in just until combined and then add in the stock.
Cook for 3-4 minutes over low to medium heat or until it becomes thick like gravy. See Note.
Add in bay leaf, parsley, thyme, salt and pepper to the sauce and mix in.
Place the chicken back into the pan, cover with a lid and cook over low heat for 25-30 minutes or until the chicken is done and cooked throughout, 165° internally.
Remove the lid and stir in the heavy cream. Serve hot.