If using mushrooms, soak them in warm water for 30 minutes, then cut into strips, discarding the tough stems. Set aside. Heat oil over medium-high heat in wok or large skillet. Saute garlic and onions until tender. Add pork, chicken and shrimp, and cook until browned. Add soy sauce, stirring to flavor. Add chicken broth and bring to boil. Add cabbage, green beans, carrots and mushrooms. Cook until vegetables are tender, yet crisp, 5-8 minutes. Add noodles, mixing gently to prevent them from breaking. Cook until liquid is absorbed and noodles are done, about 10 minutes. Remove from heat. Season with black pepper and patis. Garnish with green onions and lemon wedges.