Warm olive oil in a large skillet over medium-high heat until shimmering (about 2 minutes).

Pat chicken slices dry and season generously with salt and pepper. Cook in skillet for 3–4 minutes per side until lightly golden and cooked through.

Add sliced mushrooms to the skillet and cook until they release moisture and turn golden brown, about 5 minutes.

Add minced garlic to the skillet, sauté for 1 minute until fragrant, stirring constantly.

Pour in heavy cream and chicken broth, stirring gently to combine. Bring mixture to a low simmer and let it thicken for 3–4 minutes.

Stir in grated Parmesan until melted and adjust seasoning with salt and pepper.

Let the sauce rest off heat for 2 minutes, then serve over pasta, rice, or mashed potatoes.