Preheat your oven to 450 degrees.Clean your mushrooms and pat them dry.Put the mushrooms into a baking dish. Add in your wine, balsamic vinegar, garlic and thyme. Toss using a spoon so that the mushrooms are evenly coated.Salt and pepper your mushrooms to your liking and then add in the chunks of butter. Place the chunks evenly throughout the dish.Bake in the oven for 15-20 minutes stirring occasionally.Mushrooms are done when they are tender and golden-brown in color. A wine and butter sauce should be bubbly and forming below.Remove the mushrooms from the oven and sprinkle with fresh thyme. Serve over pasta, or as a side dish. These would go awesome with a steak!Enjoy!