This made enough for three as an appetizer and it was made from essentially leftovers.
1/2 Red Onion (Thinly Sliced)
2 Cans Beef Broth
1/2 Loaf Focaccia Bread (3/4 inch Cubes)
1/2 Cup Mozzarella (Shredded)
Saute the Onions for as long as you can, 20 or 30 minutes. The longer, on low heat, the more caramelized they get. They can be cooked at a higher heat for shorter time but that risks burning them. Also, covering them after 10 min and coming back every 5 to stir the Onions lets them steam in their own juices. Place them in a pot with the Beef Broth and leave it on low for a while. Meanwhile toast the Focaccia (or any kind of leftover bread) until they're crunchy croutons. Finally ladle the Onions and Broth into bowls, add the croutons and top with Mozzarella.