In a large skillet over medium heat, cook the bacon until crispy, about 8 minutes. Drain the slices over a paper towel-lined plate and reserve about 2 tablespoons of the fat rendered in the skillet.
Season generously with salt and pepper the chicken. Increase the heat to medium-high, then add the chicken, skin-side down. Cook until golden, about 5 -7 minutes per side. Skin needs to be crispy golden. Remove the chicken from the skillet and set aside.
Add onions and cook until soft. Stir in the mushrooms and season with salt and pepper. Cook until golden, about 5 minutes. Stir in garlic and then the chicken stock, cream, parmesan cheese, thyme and lemon juice. Bring mixture to a simmer and cook for another 5 minutes.
Return the chicken to the skillet and simmer until chicken is cooked through, about 10 more minutes more. Chop the bacon and add it to the sauce.
Garnish with fresh thyme or chopped parsley.