Cut each chicken breast in half horizontally to form 2 thin steaks, giving you 4 pieces total. Place inside a freezer bag and pound to about 2/5 inch thickness using a meat mallet or rolling pin.

Sprinkle both sides of each piece with salt, pepper, and flour. Lightly rub the flour across the surface. Shake off excess flour just before cooking.

Heat half the butter and oil in a large non-stick pan over medium-high heat. Once the butter is foamy, cook chicken for 3 to 4 minutes until golden and crispy. Flip and cook the other side for 2 minutes. Transfer to a plate.

In the same pan, add remaining butter and oil. Once melted, add shallots and garlic and cook for 1 minute, stirring.

Add the mushrooms and cook for 3 minutes, stirring regularly until softened.

Pour in the Marsala wine, turn the heat to high, and boil for 3 minutes until reduced by half.

Add the chicken broth, cream, salt, and pepper. Stir to combine, lower the heat to a gentle simmer, and cook for 3 to 5 minutes until the sauce thickens to a creamy consistency.

Nestle the chicken back into the sauce and let it sit for 30 seconds to reheat. Pour in any resting juices from the plate.

Remove from heat, sprinkle with fresh parsley, and serve immediately over mashed potatoes, pasta, rice, polenta, or with crusty bread.