This is one of my kids' favorite recipes! I could make this five times in a row and they’d never get tired of it. It’s easy to make and a real quick, hot meal for those busy nights. I will add cheese on top of the sandwiches or warm the rolls in the oven. I occasionally add mild banana peppers on top for my husband since he is a fan of spicy things.
Heat a large skillet over medium-high heat. Cook and stir beef and onion in the hot skillet until beef is completely browned, 5 to 7 minutes. Drain and discard grease. Return skillet to heat.
Stir ketchup, vinegar, brown sugar, Worcestershire sauce, and mustard into the beef mixture; simmer, stirring occasionally, until the liquid is thick, 15 to 20 minutes.
Per Serving: 199 calories; protein 13.5g; carbohydrates 16.4g; fat 9g; cholesterol 45.9mg; sodium 539.7mg.