- Preheat oven to 350 degrees F.
- In a large skillet, heat butter over medium heat. Sauté onions until beginning to soften, add garlic and continue to cook until fragrant. Stir in mushrooms and sauté until mushrooms are softened.
- Sprinkle flour evenly over mushrooms and mix until fully incorporated.
- Stir in chicken broth and half and half and increase heat to bring to simmer; salt and pepper to taste.
- Steam green beans in the microwave for 5 minutes.
- Coat large baking dish with butter or cooking spray and mix steamed green beans and cream of mushroom soup together to fully coat the beans.
- Top with cheese, cheddar cheese and french fried onions.
- Bake for 20-25 minutes until bubbly and slightly browned.