Slow Cooker French Onion Soup

Traditionally, French onion soup is made by cooking onions for a long time on the stove top over low heat until they are rich golden brown. This makes a delicious, flavorful broth, but it's also time consuming and requires you to be home for the several hours that the onions are cooking. Cooking the onions all day in a slow cooker is SO much easier and still produces a delicious, flavorful French onion soup.