Coat beef strips with 1 tbsp. Flour and salt. Brown beef strips quickly in 1 tbsp. Butter in a skillet. Add mushrooms, onion and garlic; cook until onion is crisp-tender, 3 to 4 Minuten Remove meat and mushrooms from pan. Add 2 tbsp. Butter to pan drippings; blend in 3 tbsp. Flour. Add tomato paste. Stir in broth. Stir over medium heat until thick and bubbly. Return meat and mushrooms to skillet. Stir in sour cream; cook slowly until heated through. Do not boil. Serve over hot buttered noodles.
