Heat the olive oil in a large skillet over medium-high heat.
Add the chicken slices and season with salt and pepper. Cook until browned and cooked through, about 6-8 minutes. Remove from skillet and set aside.
In the same skillet, add mushrooms. Sauté until tender and browned, about 5 minutes.
Add garlic and stir for 30 seconds until fragrant.
Pour in the cream and bring to a gentle simmer. Stir in the Parmesan.
Add the spinach and cook until wilted.
Return the chicken to the skillet and stir to coat in the sauce. Simmer for a few minutes to blend flavors.
Serve hot, optionally with a low-carb side or crusty keto bread.