Wash green beans and trim off the ends and cut into small pieces (or any size you desire)
Boil a pot of water and boil green beans for 5 minutes. After 5 minutes, drain and rinse green beans in ice cold water to retain green color.
Sauté garlic, mushrooms, salt and pepper in a skillet over medium heat until mushrooms have shrunken.
Sprinkle flour over mushrooms, stir and cook for a minute. Add milk and broth and cook until sauce thickens.
Lastly, add green beans and cook for 5 minutes. Transfer into a pretty serving dish and top with fried onions.