Cook Green Beans: Bring a large pot of salted water to a boil. Add the green beans and blanch for 3-4 minutes until tender-crisp. Drain and rinse under cold water to stop the cooking process. Set aside.
Sauté Vegetables: In a large skillet, heat the olive oil over medium heat. Add the diced onion and sauté for about 5 minutes until translucent. Stir in garlic and mushrooms, cooking for an additional 5-7 minutes until mushrooms are soft.
Mix Creamy Base: In a separate mixing bowl, combine heavy cream, vegetable broth, soy sauce, Worcestershire sauce, garlic powder, onion powder, and black pepper. Stir until well mixed.
Combine Ingredients: In the skillet with the sautéed vegetables, add the blanched green beans and half of the French fried onions. Pour the creamy mixture over them and stir to combine.
Transfer to Baking Dish: Pour the mixture into a greased 9x13 inch baking dish. Spread evenly.
Top and Bake: Sprinkle the remaining French fried onions on top for crunch. Bake in the preheated oven for 25-30 minutes, or until bubbly and golden brown on top.
Serve: Once out of the oven, let it cool for a few minutes. Garnish with fresh parsley before serving. Cut into squares or pieces for easy sharing.