Iowa's loose meat sandwich fills a soft bun with seasoned, crumbled ground beef for a simple Midwest family favorite. Budget-friendly and protein-rich, this no-fuss classic has been a staple since the 1920s.
Heat a large skillet over medium heat. Add the ground beef and use a spatula to crumble it finely as it cooks.
After 3 minutes, add the chopped onion and continue to cook, stirring frequently, until beef is no longer pink and onions are translucent (about 6 minutes). Drain excess fat if desired.
Reduce heat to medium-low. Stir in the beef broth, Worcestershire sauce, yellow mustard, salt, and pepper. Mix well to combine and simmer gently.
Continue cooking uncovered for 10–15 minutes, stirring occasionally, until the liquid mostly evaporates but the mixture remains moist and crumbly.
Taste and adjust seasoning if needed. Spoon the hot, loose beef mixture onto soft hamburger buns and serve immediately.