In a large skillet over medium-high heat, cook the ground beef and diced onion until the beef is mostly browned and the onion is softened, about 3-5 minutes.
1 pound ground beef, 1 medium onion
Stir in the ketchup, mustard, and condensed chicken gumbo soup.
¼ cup ketchup, 2 tablespoons yellow mustard, 1 can condensed chicken gumbo soup
Reduce heat to medium and simmer uncovered for 10-15 minutes, stirring occasionally, until thickened.
While the mixture simmers, toast the hamburger buns in a skillet or under the broiler. Watch carefully to prevent burning.
6 hamburger buns
Spoon the mixture onto toasted buns and serve immediately.
Notes
🥡 STORAGE: Store leftover filling in an airtight container in the refrigerator for up to 5 days♨️ REHEATING: Microwave - heat in 30-second intervals, stirring between eachStovetop - warm over medium-low heat until heated throughOven - reheat covered at 300° until warm❄️ FREEZING: Freeze the cooled filling in a freezer-safe bag for up to 2 monthsThaw overnight in the refrigerator before reheating💡 TIPS FOR BEST RESULTS: Use lean ground beef to reduce greaseSimmer uncovered to thicken properlyToast buns to prevent soggy sandwiches🍳 ALTERNATE COOKING METHODS: Slow cooker - brown meat first, then cook on low for 2-3 hoursInstant pot - sauté beef, then simmer using sauté mode♻️ LEFTOVERS: Use as a topping for baked potatoesServe over rice for a quick mealAdd to pasta for a sloppy joe twist📝 NOTES: If using higher-fat beef, drain excess grease after browningBest served hot for ideal texture and flavor