Heat olive oil in a large skillet over medium-high heat. Season the chicken breasts with salt and pepper, then cook them for 6-7 minutes per side until golden brown and cooked through. Remove from the pan and set aside.
In the same skillet, add the sliced mushrooms and cook for 3-4 minutes until tender. Add garlic and cook for another 30 seconds.
Pour in chicken broth, scraping up any bits from the bottom of the pan. Stir in the heavy cream and Parmesan cheese, bringing the sauce to a simmer. Cook for 3-4 minutes until the sauce thickens.
Return the chicken to the pan and spoon the sauce over the top. Cook for an additional 2 minutes to heat through.
Garnish with fresh parsley before serving. Serve with your favorite side.
Notes
For a richer flavor, use full-fat cream.
For an extra creamy texture, stir in a bit more cheese.
If you prefer a thicker sauce, let it reduce longer on low heat.