Cook Bacon, set aside to cool
Dice onion
In bacon grease saute onion for 1 minute
Add beef and cook until no longer pink, drain liquid
Add ketchup, mustard, worcestershire, salt and pepper, Mix thoroughly
Mix cornstarch and beef broth together, add to meat
Add shredded cheddar and crumbled bacon
Serve on toasted Brioche with a slice of cheddar