These French Onion Joes feature just four simple ingredients, including ground beef, and are an easy weeknight sandwich option.
Brown ground beef in a skillet; drain excess grease.
In a bowl, mix water and flour together until smooth.
Add cooked ground beef, french onion soup, and water/flour mixture back to the skillet. Simmer over medium heat until thickened.
Serve on buns. Optional toppings include Colby cheese, mustard or pickles.