Heat large nonstick skillet over medium heat until hot. Place beef steaks in skillet; cook 10 to 13 minutes for medium rare (145°F) to medium (160°F) doneness, turning occasionally. Remove to platter, season with salt and pepper, as desired. Keep warm.
Heat butter in same skillet over medium heat until melted. Add mushrooms and shallots; cook and stir 3 to 5 minutes or until mushrooms are tender and browned. Add beef broth and thyme to skillet, stirring until browned bits attached to bottom of pan are dissolved; bring to a boil. Combine cornstarch and water in small bowl; stir into mushroom mixture. Cook 2 minutes or until sauce thickens, stirring occasionally. Season with salt and pepper, as desired.
Serve steaks with sauce.
Nutrition information per serving: 282 Calories; 117 kcal Calories from fat; 13 g Total Fat; 6 g Saturated Fat; 5 g Monounsaturated Fat; 97 mg Cholesterol; 365 mg Sodium; 5 g Total Carbohydrate; 0.4 g Dietary Fiber; 35 g Protein; 2.6 mg Iron; 11.4 mg Niacin; 0.8 mg Vitamin B6; 2 mcg Vitamin B12; 6.4 mg Zinc; 44.4 mcg Selenium; 136.9 mg Choline;