Preheat your oven to 350°F (175°C).
Blanch the green beans in boiling water for 3 minutes, then drain and rinse with cold water.
In a large mixing bowl, combine cream of mushroom soup, milk, and half of the fried onions.
Stir in the cooked green beans and half of the shredded cheese.
Season with salt and pepper to taste.
Transfer the mixture to a greased baking dish.
Top with the remaining cheese and crispy fried onions.
Bake in the preheated oven for 25-30 minutes until bubbly and golden brown.
Remove from the oven and let cool for a few minutes.
Serve warm and enjoy!