Cut meat into 2 inch thin strips and season with salt and pepper. Heat butter in large skillet and brown meat in 2 batches. Set aside meat and juices in bowl. In same pan, add olive oil and onion. Sauté 3-5 minutes over medium heat until soft. Turn up heat to medium high and add 1-2 T olive oil or butter. Add mushrooms, thyme and cook until soft 5-7 minutes.
Reduce heat to medium and add red wine to deglaze pan. Add flour to thicken sauce and stir well. Add broth, stir well and continue to cook for 8-10 minutes. Add meat and Dijon mustard and simmer for 3-5 minutes longer. Remove from heat, stir in sour cream, 1 T dill and mix well. Serve over egg noodles and garnish with an additional tablespoon of sour cream and remaining dill. Serves 4-6.