Preheat oven to 375 degrees and spray a 2-qt casserole dish with non-stick cooking spray.

Place a large skillet over medium-high heat and add 2 Tbsp unsalted butter. Add chicken pieces and season with salt, pepper, garlic powder and thyme. Cook chicken about 5–6 minutes until lightly browned on all sides and nearly cooked through. Arrange chicken evenly across the bottom of prepared baking dish and set aside.

Return skillet to heat and add additional 2 Tbsp unsalted butter and allow it to melt. Add the mushrooms and season lightly with salt and pepper. Cook the mushrooms about 7–8 minutes, stirring occasionally, until they have released their liquid and begin to brown.

Sprinkle the mushrooms with flour and stir to combine. Allow flour to cook for about 20–30 seconds then add chicken broth and stir to dissolve flour. Bring to a boil then reduce heat to medium-low and simmer for 3 minutes.

Add cream cheese in small pieces and stir until it has melted into the sauce. Remove from heat and add shredded smoked Gouda and stir until cheese is completely melted and sauce is smooth. Season to taste with salt and pepper then pour mushroom cheese sauce over chicken in prepared baking dish.

Sprinkle panko breadcrumbs over the top of the dish and bake 20–25 minutes until bubbly and golden. Remove from oven and allow the dish to sit for 10 minutes before serving. Sprinkle with chopped parsley if desired and enjoy!