1. Preheat oven to 375°F (190°C) and lightly grease a casserole dish.
2. In a large bowl, mix cream of mushroom soup, milk, garlic powder, salt, and pepper until smooth.
3. Stir in the blanched green beans and half the fried onions. Mix well and pour into the casserole dish.
4. Sprinkle shredded cheddar cheese evenly over the top, followed by the remaining fried onions.
5. Bake for 20-25 minutes, or until the cheese is melted and bubbly, and the onions are golden.
6. Serve hot as a side dish for any meal or holiday feast.