Slice the chicken breasts into thin pieces or bite-sized strips. Season both sides with salt, black pepper, and dried thyme.
Heat olive oil in a large pan over medium heat. Add the chicken and cook for 4–5 minutes on each side until golden and fully cooked. Remove the chicken from the pan and set aside.
In the same pan, add butter. Once melted, add the sliced mushrooms. Cook for about 4–5 minutes until the mushrooms become soft and lightly browned.
Add the minced garlic and cook for 30 seconds until fragrant. Stir gently so the garlic does not burn.
Pour in the chicken broth and stir well, scraping the bottom of the pan to mix the flavors.
Add the heavy cream and parmesan cheese. Stir slowly and let the sauce simmer for 2–3 minutes until slightly thick and creamy.
Return the cooked chicken to the pan. Mix everything together and cook for another 2 minutes so the chicken absorbs the creamy sauce.
Turn off the heat and sprinkle chopped fresh parsley on top.
Serve warm with rice, pasta, mashed potatoes, or bread.