Preheat your oven to 375°F (190°C).

In a skillet, melt butter over medium heat. Add garlic and sauté until fragrant, about 1 minute.

Add the chopped mushrooms, thyme, parsley, salt, and pepper. Cook until mushrooms are browned and any moisture has evaporated, about 5-7 minutes.

In a bowl, mix the cooked mushrooms with cream cheese and mozzarella cheese until well combined.

Carefully cut a pocket into each chicken breast and stuff it with the mushroom cheese mixture.

Place the stuffed chicken breasts in a greased baking dish and sprinkle with grated Parmesan cheese.

Bake for 25-30 minutes, or until the chicken is cooked through and juices run clear.

Garnish with fresh parsley before serving.