Pound chicken to an even 1/2-inch thickness; pat dry and season with salt, pepper and garlic powder.

Heat 2 tablespoons of butter in a large skillet over medium-high heat.

Add the chicken breasts and cook for 5-6 minutes per side until golden brown and cooked through (internal temperature of 165°F). Remove to a plate.

In the same skillet, add 1 more tablespoon of butter and 8 oz of sliced baby bella mushrooms.

Cook the mushrooms for 5-6 minutes until browned and tender.

Add 3 cloves of minced garlic and cook for 30 seconds until fragrant.

Pour in ½ cup of chicken broth and scrape up any browned bits from the bottom of the pan.

Reduce heat to medium and stir in 1 cup of heavy cream, 1 teaspoon of Dijon mustard, and ½ teaspoon of dried thyme.

Simmer for 3-4 minutes until the sauce begins to thicken.

Remove the pan from heat and stir in Swiss cheese a handful at a time until smooth.

Return the chicken breasts to the pan, spooning the sauce over the top.

Warm gently for 2-3 minutes without boiling.

Taste and adjust seasoning with salt and pepper as needed.

Garnish with optional parsley and serve.