Slice each chicken breast horizontally to create four thin cutlets.

Season both sides with salt and black pepper.

Lightly coat each piece with flour, shaking off any excess.

Heat 1 tablespoon of butter in a large skillet over medium-high heat.

Cook the chicken for about 2½ minutes per side until golden brown and cooked through. Transfer to a plate and keep warm.

In the same skillet, melt the remaining butter.

Add the sliced mushrooms and cook for about 4 minutes until lightly browned.

Stir in the minced garlic and cook for another minute until fragrant.

Pour in the chicken stock to deglaze the pan, scraping up the browned bits. Simmer for about 1 minute.

Add the remaining chicken stock and heavy cream. Reduce the heat to medium and simmer for 2–3 minutes until the sauce begins to thicken.

Stir in the grated Parmesan cheese until smooth and creamy.

Taste and adjust the seasoning with salt and pepper if needed.

Return the chicken to the skillet and simmer for 30 seconds to warm through.

Garnish with chopped chives or parsley and serve your Chicken Breast in Creamy Mushroom Sauce immediately.