Preparation of Chicken: In a shallow dish, combine the flour, garlic powder, salt, and pepper. Coat each chicken breast evenly with the flour mixture, ensuring complete coverage on all sides.
Cooking the Chicken: In a large skillet, heat the olive oil and butter over medium heat until hot but not smoking. Place the chicken in the skillet and cook for approximately 2 minutes on each side, or until the chicken is golden and slightly crisp. Once cooked, remove the chicken from the skillet and set aside on a plate.
Sauce Preparation: Utilize the same skillet; add an additional tablespoon each of olive oil and butter. Introduce the sliced mushrooms and season with salt and pepper. Sauté for 3 to 5 minutes until the mushrooms are golden brown and have released their moisture.
Developing the Sauce: Add the minced garlic to the mushrooms, cooking briefly for about 30 seconds until fragrant. Deglaze the skillet with chicken broth, scraping up any browned bits from the bottom. Pour in the heavy cream and bring to a gentle simmer, allowing the sauce to reduce slightly before incorporating the grated Parmesan cheese. Adjust seasoning as necessary.
Final Assembly: Return the chicken breasts to the skillet, nestling them into the sauce. Spoon some of the sauce over the top of the chicken to ensure it is well coated. Continue to cook on low heat for a few minutes to allow the chicken to absorb the flavors of the sauce.
Presentation: Serve the chicken immediately, garnished with chopped parsley. This dish pairs well with mashed potatoes, steamed vegetables, or over a bed of pasta to complement the creamy sauce.