French Onion Sloppy Joes Recipe: Savory, Caramelized Beef Sandwiches

These French Onion Sloppy Joes put a tasty spin on the classic sloppy joe by combining caramelized onions, seasoned ground beef, and the rich flavor of French onion soup mix. They’re easy to prepare and the slow cooker does most of the work, producing a savory, slightly sweet filling that’s perfect on buns or served over rice or mashed potatoes.

French Onion Sloppy Joes on a bed of fries.

French Onion Sandwiches

This recipe blends classic French dip flavors with a sloppy joe base for a comforting, family-friendly dinner. Thinly sliced onions are cooked with ground beef, then combined in a crockpot with beef broth, French onion soup mix, and a few simple seasonings. Let it simmer until the flavors meld and the sauce thickens.

Ingredients Needed

  • Ground beef: Use lean ground beef for best texture and flavor.
  • Oatmeal: Quick-cooking oats act as a natural thickener.
  • Worcestershire sauce: Adds depth and a savory, slightly smoky note.
  • Seasonings: Garlic powder and black pepper are used here; adjust or add herbs to taste.
  • Provolone cheese: Melts nicely—mozzarella or Muenster can be substituted.
French Onion Sloppy Joes on a blue striped table cloth.

How To Make French Onion Sloppy Joes

  • Brown the beef and onions. In a large skillet, sauté ground beef with thinly sliced onion over medium heat until the beef is fully cooked. Drain excess grease, then transfer the mixture to a slow cooker.
  • Make the sauce. Add quick-cooking oatmeal, beef broth, beefy onion soup mix, Worcestershire sauce, garlic powder, and black pepper to the slow cooker. Stir until everything is well combined.
  • Slow cook. Cover and cook on low for 3–4 hours, until the flavors meld and the sauce thickens. Just before serving, place provolone slices on top, cover for about 5 minutes to let the cheese melt, then spoon the mixture onto buns and serve.
Cooking the beef and onions.
Adding the beef and mix.
Melting the cheese on top.
French Onion Sloppy Joes in a grey tray.

What To Serve with French Onion Sloppy Joes

These sloppy joes are versatile—serve them on brioche or slider buns with fries or a crisp salad. They’re also delicious spooned over rice or mashed potatoes for a heartier meal. Add pickles or a simple slaw for a bright contrast to the rich, savory filling.

Tips & Tricks

  • Storing: Refrigerate leftovers in an airtight container for up to 3 days, or freeze for up to 3 months.
  • Boost the flavor: Add a clove of fresh minced garlic when cooking the beef for a brighter garlic note.
  • Adjust consistency: If it becomes too thick, stir in about 1/2 cup of beef broth to reach the desired texture.
A hand holding a French Onion Sloppy Joes.

More Sloppy Joe Recipes

  • Rodeo Sloppy Joes
  • Garlic Bread Sloppy Joes
  • Sloppy Joe Grilled Cheese
  • Mississippi Sloppy Joes
  • Philly Cheesesteak Sloppy Joes
French Onion Sloppy Joes feature
5 from 3 votes

French Onion Sloppy Joes

Savory, slightly sweet, and cheesy ground beef in a thick French onion–flavored sauce.
Servings: 6 people
Prep: 15 mins
Cook: 4 hrs
Total: 4 hrs 15 mins
Print
Rate

Ingredients

  • 2 pounds lean ground beef
  • 1 large onion, sliced thin
  • 1/2 cup quick cooking oatmeal
  • 1 1/3 cups beef broth
  • 1 ounce beefy onion soup mix
  • 1 Tablespoon Worcestershire sauce
  • 1/2 teaspoon garlic powder
  • 1/2 teaspoon black pepper
  • 6 slices provolone cheese
  • Buns

Instructions

  • In a large skillet, sauté the ground beef with the thinly sliced onion over medium heat until the beef is cooked through. Drain any excess grease and transfer the mixture to a slow cooker.
  • Add the quick-cooking oatmeal, beef broth, beefy onion soup mix, Worcestershire sauce, garlic powder, and black pepper to the slow cooker. Stir well to combine.
  • Cover and cook on low for 3–4 hours. Just before serving, place provolone slices on top, cover for about 5 minutes to melt the cheese, and then serve on buns.

Last Step:

Please leave a rating and comment letting us know how you liked this recipe — your feedback helps us continue sharing great recipes.

Nutrition

Serving: 6 g |
Calories: 495 kcal |
Carbohydrates: 9 g |
Protein: 33 g |
Fat: 36 g |
Saturated Fat: 15 g |
Cholesterol: 120 mg |
Sodium: 755 mg

Did You Make This?

Leave a comment & rating below or tag us on social media if you try the recipe!
French Onion Sloppy Joes feature