Name: French Onion Beef Sloppy Joes
Prep time: 10 min
Cook time: 20 min
Total time: 30 min
Cuisine: American
Ingredients: 1 pound ground beef; 2 large yellow onions, thinly sliced; 2 tablespoons salted butter; 2 cloves garlic, minced; 1/2 cup beef broth; 1 tablespoon Worcestershire sauce; 1/2 teaspoon dried thyme; 1/2 teaspoon salt; 1/4 teaspoon black pepper; 1 cup shredded mozzarella or Gruyere cheese; 6 brioche slider buns

If you’re craving something cozy, hearty, and just a little indulgent, these French Onion Beef Sloppy Joes are calling your name. A savory twist on the classic sloppy joe, this version is loaded with deeply caramelized onions, richly seasoned beef, and a melted blanket of cheese all nestled into soft brioche buns. It’s comfort food with a gourmet edge.

These sandwiches are a weeknight hero—ready in under 30 minutes and made with simple pantry staples. But don’t let the speed fool you. The depth of flavor from the onions and a splash of Worcestershire sauce gives them an irresistible richness that’s perfect for family dinners, game days, or feeding a hungry crowd.

What Kind of Onion Should I Use?

To get that sweet, caramelized flavor that defines French onion recipes, yellow onions are your best bet. They hold up beautifully during the slow cooking process and develop a deep, rich sweetness without becoming mushy. If you’re in a pinch, white onions can substitute, but avoid red onions as their sharper bite and color won’t blend as well with the rich, beefy flavor.

Ingredients for the French Onion Beef Sloppy Joes

Ground Beef: The star of the show. Go for 85/15 for the perfect balance of flavor and minimal grease.

Yellow Onions: Slowly caramelized to bring that deep, sweet-savory base.

Garlic: Just a couple of cloves to round out the flavor with a savory punch.

Beef Broth: Helps deglaze the pan and enhance the meaty flavor.

Worcestershire Sauce: Adds depth and a subtle tangy-salty kick.

Thyme: A small sprinkle of dried thyme gives that hint of herbiness French onion soup is known for.

Salted Butter: Essential for caramelizing the onions and adding that rich, luxurious feel.

Mozzarella or Gruyère Cheese: For a creamy, melty finish that ties it all together.

Brioche Slider Buns: Buttery, soft, and the perfect vessel to hold that flavorful filling without falling apart.

How To Make the French Onion Beef Sloppy Joes

Step 1: Caramelize the Onions

Melt butter in a large skillet over medium heat. Add the thinly sliced yellow onions with a pinch of salt and cook low and slow for about 15-20 minutes, stirring occasionally. You’re looking for golden, soft, deeply flavorful onions.

Step 2: Add Garlic and Beef

Once the onions are caramelized, stir in minced garlic and cook for another minute. Then add the ground beef and break it up with a wooden spoon. Cook until browned and no longer pink.

Step 3: Build the Flavor Base

Pour in the beef broth and Worcestershire sauce, then sprinkle in the thyme. Let everything simmer together for 5-7 minutes, reducing slightly so the mixture thickens.

Step 4: Melt the Cheese

Turn off the heat and layer shredded mozzarella or Gruyère over the beef mixture. Cover the skillet with a lid for a few minutes until the cheese melts into gooey perfection.

Step 5: Assemble and Serve

Toast your brioche buns lightly if desired. Spoon the beef mixture onto the bottom bun, crown it with the top, and serve warm. Optional: sprinkle with chopped parsley for a fresh finish.

How to Serve and Store These Sloppy Joes

These sliders are best served warm and fresh, ideally right after assembling. Pair them with a crisp side salad, kettle chips, or roasted potatoes for a full meal. For parties, they hold up well on a platter with the filling kept warm in a slow cooker.

To store leftovers, refrigerate the meat mixture in an airtight container for up to 3 days. Reheat on the stovetop or in the microwave, and toast fresh buns to assemble when ready to eat. Avoid freezing assembled sandwiches—instead, freeze the meat mixture alone for up to 2 months.

Frequently Asked Questions

Can I make this ahead of time?

Yes! The beef mixture can be made a day in advance and reheated. Just wait to assemble until you’re ready to serve.

What cheese melts best for this recipe?

Gruyère gives the most classic French onion flavor, but mozzarella is a great melty alternative.

Can I make it spicy?

Sure thing! Add a pinch of crushed red pepper flakes or a dash of hot sauce to the beef while cooking.

What if I don’t have Worcestershire sauce?

You can sub with soy sauce and a splash of balsamic vinegar to get a similar savory depth.

Are there vegetarian options?

Absolutely! Try using plant-based ground beef and vegetable broth. Caramelized onions and cheese still bring all the flavor.

Can I use regular hamburger buns?

Yes, but brioche or slider buns hold up better to the juiciness of the filling and offer a slightly sweet contrast.

Want More Beef Dinner Ideas?

If these French Onion Beef Sloppy Joes hit the spot, you might enjoy these savory mains too:

For more weeknight inspiration and daily recipe fun, check out my Pinterest boards at Life with Nina on Pinterest.

📌 Save this recipe to your Pinterest dinner board so you can come back to it any time.

And let me know in the comments how yours turned out. Did you go with Gruyère or mozzarella? Toast the buns or go soft and warm?

I love hearing how others make these recipes their own. Questions are welcome too—let’s help each other cook with flavor and confidence.

French Onion Beef Sloppy Joes

Author: Nina Johnson
Prep Time: 10 minutes
Cook Time: 20 minutes
Total Time: 30 minutes
Yield: 6 sliders 1x
Category: Dinner
Method: Skillet
Cuisine: American

Print Recipe

Description

These French Onion Beef Sloppy Joes combine all the rich, savory flavor of French onion soup with the ease and heartiness of a classic sloppy joe. Perfect for busy weeknights, these sandwiches feature caramelized onions, juicy ground beef, melty cheese, and buttery brioche buns. Comfort food never tasted so good.

Instructions

1. In a large skillet over medium heat, melt the butter and add sliced onions with a pinch of salt.
Cook the onions low and slow, stirring occasionally, until caramelized (15–20 minutes).
Add minced garlic and sauté for 1 minute until fragrant.
Add ground beef and cook until browned and no longer pink.
Stir in beef broth, Worcestershire sauce, thyme, salt, and pepper.
Simmer for 5–7 minutes, letting the mixture reduce and thicken.
Sprinkle cheese over the beef mixture, cover the pan, and allow the cheese to melt.
Toast the brioche buns if desired, then assemble the sloppy joes
Garnish with chopped parsley (optional) and serve warm.