Season the chicken with salt and pepper. Heat a skillet over medium-high heat and sear the chicken until golden brown on both sides. Remove and set aside.
In the same skillet, sauté the garlic and shallots until fragrant. Add the fresh spinach and cook until wilted.
Pour in the heavy cream and stir in the Parmesan cheese. Simmer for a few minutes until the sauce thickens.
Return the chicken to the skillet and spoon the sauce over it. Let everything cook together for 5 more minutes.
Serve hot over pasta, rice, or with crusty bread.