Sloppy Joes are a very popular, messy sandwich! Not only do they taste delicious, but the ingredients are generally inexpensive. Traditionally, the Sloppy Joe is made with ground beef, onions, garlic, bell pepper, Worcestershire sauce, tomato sauce or ketchup, and seasoning on a hamburger bun or roll. What a combo! Of course, there is no right or wrong way to make this sandwich. Some people have substituted beef for chicken, or a plant-based meat.