Season chicken breasts with salt and pepper. Heat olive oil in a large skillet over medium-high heat.
Sear chicken for 4-5 minutes per side until golden brown. Remove and set aside.
In the same skillet, melt butter and sauté garlic, onion, and mushrooms until softened, about 5 minutes.
Deglaze the pan with white wine, scraping up brown bits. Simmer for 2 minutes.
Add chicken broth, thyme, and cream. Stir well and return chicken to the skillet.
Simmer on low heat for 8-10 minutes, until chicken is cooked through and sauce thickens slightly.
Garnish with parsley before serving.