Melt butter in a large saucepan over medium heat.
Whisk in the flour until smooth.
Add milk, dried onions, salt and pepper.
Cook and whisk until it starts to thicken.
Pour the green beans in a 9x13 baking dish.
Sprinkle with salt.
Pour the white sauce over the beans and mix it in.
Top with French fried onions.
Bake at 350 for 45 min until bubbly.