Preheat the oven to 350°F.
Frozen green beans require no cutting and have a tender-crisp texture. They should be boiled for about 3-5 minutes, and you’ll need to add extra salt.
Bring a medium pot of salted water to a boil. Add the frozen green beans and boil until tender crisp, about 2 to 3 minutes.
In a large bowl, combine green beans with soup, milk, soy sauce, pepper, salt, 1 cup of crispy onions, and cheese if using (see notes). Transfer to a 2-quart baking dish.
Bake uncovered for 30 to 35 minutes or bubbly.
Remove from oven and stir. Top with remaining onions and return to oven for an additional 10 minutes or until golden.
