Combine the soup, broth, milk and seasonings, in the slow cooker. Add in the green beans, and stir until they are covered with all of the ingredients.
Cover and cook on high for about 3 hours.
After three hours, add ½ of the fried onions, and stir to combine them with the green beans. Replace the lid on the cooker, and allow them to cook on low for an additional 15 minutes.
The green beans will be done when they are tender.
Top with green beans with the remainder of the dried onions before serving.
I used exactly 1 ½ pounds of fresh green beans. The cream of mushroom soup will thicken as it cools. We love the fried onions, but the amount can be lowered or increased based on preference. You can also add additional mushrooms to the casserole while it cooks, or add crumbled bacon on top of the onions.