Remove fat from steak and slice meat across the grain into bite-size pieces. Spray a large nonstick skillet with cooking spray. Add oil and warm over medium heat. Add meat and brown on both sides. Stir in garlic, mushrooms, and onion; cook for 5 minutes. Add margarine and cook until melted. Stir in 2 tablespoons of flour until liquid forms a paste. Stir in Worcestershire sauce, pepper, dill weed, and beef broth. Continue cooking uncovered for 10 minutes, stirring frequently. Mix remaining 1 tablespoon of flour into the sour cream, then add to meat mixture. Cook for 5 minutes, stirring frequently, but do not boil. Toss in steamed broccoli and cooked pasta.