Combine eggs, sprouts, onions, flour & salt thoroughly. Heat wok or heavy skillet over moderate heat until hot. Add 2 T oil and heat. Ladle mixture into 4 mounds in wok. Using a spatula, gently flatten the mounds. Cook until the underside is brown, turn over, add the remaining 2 T oil, and continue cooking for 6 to 7 minutes. Remove and drain. Lightly score the top of each patty with an "X" and arrange on serving platter. Pour gravy over all and serve. To make gravy: Mix oil & flour in a pre-heated skillet and cook over medium heat to make a roux. Gradually stir in broth along with remaining gravy ingredients, cooking until a gravy consistency is reached. To vary the gravy, add diced cooked chicken, pork or shrimp to it. From Chef Chu's Distinctive Cuisine of China, Harper & Row.