Preheat the oven to 355°. Mix together the cream of mushroom and milk. Set aside.
In a pan, sauté onions until translucent then stir in the green beans. Add the cream of mushroom and milk mixture. Season with salt and pepper. Stir in a small amount of French fried onions.
Place the whole thing in a baking pan. Top with the remaining French fried onions. Bake it in the oven for 15-20 minutes.