Preheat your oven to 350°F (175°C).
Blanch the green beans in boiling water for 5 minutes, then drain and rinse with cold water.
In a large mixing bowl, combine the cream of mushroom soup, milk, soy sauce, garlic powder, and season with salt and pepper.
Add the blanched green beans to the soup mixture and stir until well coated.
Transfer the mixture into a greased casserole dish.
Sprinkle crispy fried onions over the top of the green bean mixture.
Bake in the preheated oven for 25-30 minutes, or until the casserole is bubbling.
Remove from the oven and let it sit for a few minutes before serving.