01 - Season the chicken breasts on both sides with salt and pepper, ensuring even coverage.
02 - Heat olive oil in a large skillet over medium-high heat. Add chicken breasts and cook for 5-6 minutes per side until golden brown and cooked through. Transfer to a plate and keep warm.
03 - Reduce heat to medium and add butter to the same skillet. Once melted, add mushrooms and sauté for 4-5 minutes until browned and tender.
04 - Add garlic and thyme to the skillet; cook for 1 minute until fragrant, being careful not to burn the garlic.
05 - Pour in chicken stock, scraping up any browned bits from the bottom of the pan. Simmer for 2 minutes to reduce slightly.
06 - Stir in heavy cream and Parmesan cheese. Simmer for 2-3 minutes until sauce thickens and coats the back of a spoon.
07 - Return chicken to the skillet, nestling it into the sauce. Simmer for 2-3 more minutes until heated through. Garnish with chopped parsley and serve hot.