This casserole based on a favorite soup will satisfy any comfort food craving. Partially cooking the egg noodles allows them to soak up the flavorful sauce without becoming too soft.
Preheat the oven to 375ºF. Butter a 3-quart casserole dish.
Bring a large pot of generously salted water to a boil. Add the egg noodles and cook until al dente, about 4 minutes. Strain.
Meanwhile, heat 2 tablespoons of the butter in a large Dutch oven or pot over medium-high heat. Add the mushrooms and cook, stirring occasionally, until browned all over, about 3 minutes. Season with 1/2 teaspoon salt and a few grinds of pepper. Transfer to a small bowl and set aside.
Lower the heat to medium and melt the remaining 4 tablespoons butter in the Dutch oven. Whisk in the flour to form a loose paste. Stir in the onions, carrots, celery and thyme and season with 1/2 teaspoon salt and a few grinds of pepper. Cook for 5 minutes to soften, then add the wine. Whisk for 30 seconds, then add the chicken broth and heavy cream. Bring to a boil, reduce heat and simmer for 10 minutes. Remove the thyme sprigs; fold in the noodles, mushrooms, chicken and parsley and season with salt and pepper. Transfer to the buttered casserole dish and top with the Gouda.
Bake until bubbly and brown on top, 40 to 45 minutes.