Go Back
A close-up features a delicious serving of French Onion Beef Sloppy Joes, showcasing the melted cheese and caramelized onions.

French Onion Beef Sloppy Joes

These French Onion Beef Sloppy Joes combine the savory flavors of French onion soup with the comforting messiness of a classic sloppy joe. Caramelized onions, ground beef, and Gruyere cheese create a flavor explosion that's easy to make and perfect for a weeknight dinner. This recipe is a delicious twist on a classic comfort food.
Print Recipe Pin Recipe
Prep Time 20 minutes
Cook Time 1 hour
Total Time 1 hour 20 minutes
Servings: 6
Course: Main Course
Cuisine: American
Calories: 550
Ingredients Equipment Method Notes

Ingredients
  

  • 2 large yellow onions, thinly sliced
  • 2 tablespoons olive oil
  • 2 tablespoons butter
  • 1 teaspoon sugar
  • 1/2 teaspoon salt
  • 1/4 teaspoon black pepper
  • 1 pound ground beef
  • 1 cup beef broth
  • 1/4 cup Worcestershire sauce
  • 1 tablespoon tomato paste
  • 1 teaspoon Dijon mustard
  • 1/2 teaspoon garlic powder
  • 1/4 teaspoon onion powder
  • Salt to taste
  • Pepper to taste
  • 6-8 hamburger buns, toasted
  • 1 cup shredded Gruyere cheese or Swiss cheese
  • Fresh thyme for garnish optional

Equipment

  • Large Skillet
  • Spatula
  • Measuring cups and spoons
  • Toaster
  • Broiler (optional)
  • Cutting board
  • Knife
  • Serving Spoon

Method
 

  1. Heat olive oil and butter in a large skillet over medium-low heat.
  2. Add sliced onions, sugar, salt, and pepper.
  3. Cook, stirring occasionally, for 30-45 minutes, or until the onions are deeply golden brown and caramelized. Be patient – this takes time! If they start to burn, lower the heat. The key is low and slow.
  4. Remove onions from the skillet and set aside.
  5. In the same skillet, brown the ground beef over medium-high heat. Drain off any excess grease.
  6. Stir in beef broth, Worcestershire sauce, tomato paste, Dijon mustard, garlic powder, and onion powder. Season with salt and pepper to taste.
  7. Bring to a simmer and cook for 10-15 minutes, or until the sauce has thickened slightly.
  8. Add the caramelized onions to the beef mixture.
  9. Stir well to combine.
  10. Reduce heat to low and simmer for another 5-10 minutes to allow the flavors to meld together beautifully.
  11. Spoon the French Onion Beef mixture onto the toasted hamburger buns.
  12. Top with shredded Gruyere cheese.
  13. If desired, place the assembled Sloppy Joes under the broiler for a minute or two to melt the cheese (watch carefully to prevent burning!).
  14. Garnish with fresh thyme, if desired, and serve immediately.

Notes

You can caramelize the onions up to 2 days in advance and store them in the refrigerator. You can also prepare the beef mixture up to 1 day in advance and store it in the refrigerator. When you're ready to assemble the Sloppy Joes, simply reheat the beef mixture and follow the instructions. Store leftover French Onion Beef mixture in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stovetop or in the microwave. For variations, add a pinch of red pepper flakes, sauté sliced mushrooms, or use ground turkey or chicken instead of ground beef.