01 - Evenly sprinkle kosher salt, ground black pepper, and dried thyme over both sides of each chicken breast.
02 - Heat olive oil in a large skillet over medium-high heat. Sear chicken breasts for 4–5 minutes per side until golden brown and cooked through. Transfer to a plate and cover lightly with foil.
03 - Add chopped onion and sliced mushrooms to the same skillet. Sauté over medium heat for 5 minutes until softened, stirring occasionally. Add minced garlic and cook for 1 additional minute until fragrant.
04 - Pour in chicken broth and bring to a simmer, scraping any browned bits from the skillet. Allow to reduce by half, about 3–4 minutes.
05 - Reduce heat to medium-low and stir in heavy cream. Simmer gently for 3–4 minutes until sauce is slightly thickened.
06 - Return seared chicken breasts to the skillet. Spoon sauce over the top. Simmer for 3–4 minutes, until chicken is heated through and the sauce coats the chicken.
07 - Sprinkle with chopped parsley just before serving.