Name: French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe
Prep time: 15 min
Cook time: 55 min
Total time: 1 h 10 min
Cuisine: American
Ingredients: 9 slider buns; 3 tbsp butter, divided; 2 yellow onions, thinly sliced; ½ tsp salt; ½ tsp thyme; 3 tbsp prepared horseradish; 2 tbsp mayonnaise; 9 ounces thinly sliced roast beef; 7 ounces thinly sliced provolone cheese; ¼ tsp garlic powder; 1 tsp finely chopped parsley; 2 tbsp butter; 1 clove garlic, minced; 1 tbsp all-purpose flour; 1 ½ cups beef broth; 1 tbsp Worcestershire sauce; Salt and pepper, to taste

Jump to Recipe· 4.2 from 32 reviews

If you're looking for a crowd-pleasing appetizer or a cozy meal that bursts with flavor, the French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe will quickly become your new favorite. Picture buttery, soft slider buns piled high with tender roast beef, layers of gooey provolone, and sweet, deeply caramelized onions. All baked to melty, golden perfection and paired with a rich, savory au jus that invites you to dip each bite into pure indulgence. This dish is comfort food elevated, perfect for sharing with friends or savoring on a quiet night in.

Ingredients You'll Need

The image shows a top-down view of ingredients neatly arranged on a white marbled surface. In the lower left corner, there is a square cloth holding nine golden brown soft bread rolls in three rows and columns. To the top left, a small white bowl filled with thinly sliced white onions and a small white dish with black pepper next to it. Moving right, a white oval plate holds two layers of pale yellow cheese slices and several slices of pink roast beef with seared edges. Below these, from left to right, are four small white bowls containing mayonnaise, a creamy white sauce, more butter, and chopped green herbs. Further right, there are three more small white dishes holding light brown sugar, dark brown soy sauce, and finely chopped yellow garlic. In the bottom right corner, there is a glass measuring cup with a peeled whole onion inside. A woman’s hand is not shown but implied to be taking the photo. photo taken with an iphone --ar 4:5 --v 7

Don't be intimidated by the rich taste of these sliders—each ingredient is straightforward yet plays a crucial role in creating that unforgettable balance of flavors and textures. From the juicy roast beef to the slow-cooked onions and the velvety cheese, everything comes together effortlessly.

9 slider buns: Soft and buttery, they hold all the goodness without falling apart.

3 tablespoon butter: Essential for caramelizing the onions to sweet perfection.
2 yellow onions, thinly sliced: Slowly caramelized to bring out their natural sweetness and depth.
½ teaspoon salt: Enhances the flavor of the caramelized onions and au jus.

½ teaspoon thyme: Adds a subtle earthy herbaceous note to the onions.
3 tablespoon prepared horseradish: Brings a gentle kick that cuts through the richness of the beef.
2 tablespoon mayonnaise: Creates a creamy, tangy spread when mixed with horseradish.

9 ounces thinly sliced roast beef: Tender and flavorful, the star protein of the sliders.
7 ounces thinly sliced provolone cheese: Melts beautifully and adds a mild, creamy texture.
2 tablespoon melted butter: For brushing the buns to achieve a golden, crispy top.

¼ teaspoon garlic powder: Gives a subtle garlic essence to the butter glaze.
1 teaspoon finely chopped parsley: Adds a pop of freshness and color.
2 tablespoon butter: Used to start the savory au jus sauce.

1 clove garlic, minced: Infuses the au jus with aromatic garlic flavor.
1 tablespoon flour: Thickens the au jus to a luscious consistency.
1 ½ cups beef broth: The base of the au jus, bringing rich beefy flavor.

1 tablespoon sauce: Adds a complex umami depth to the dipping sauce.

How to Make French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe

Step 1: Caramelize the Onions

Start by melting butter in a skillet over medium heat, then add thinly sliced onions seasoned with salt and thyme. Patience is key here, as you’ll want to cook them slowly for about 30 to 45 minutes. This slow caramelization process transforms the onions into sweet, tender ribbons that bring incredible richness to your sliders. Keep stirring occasionally to prevent burning, and add a splash of water if they look dry—it’s like liquid gold in your pan.

Step 2: Prepare the Oven and Horseradish Mayo

Preheat your oven to 350 degrees Fahrenheit while the onions work their magic. Meanwhile, whisk together prepared horseradish and mayonnaise in a small bowl—this creamy, tangy spread will give the sliders a delightful bite that complements the savory beef perfectly.

Step 3: Assemble the Sliders

Slice the buns horizontally, but keep the bottoms connected to form one sheet and do the same with the tops. Place the bottom halves on a baking sheet and layer the roast beef evenly, followed by a generous amount of provolone cheese and the luscious caramelized onions. Spread the horseradish mayo over the top halves, then close the sliders by pressing the top layer onto the fillings. This structure keeps everything in place during baking and makes serving a breeze.

Step 4: Glaze and Bake

Mix melted butter with garlic powder and chopped parsley, then brush this flavorful glaze over the top of the buns. Cover them with tin foil to trap the moisture and bake for 20 minutes so the cheese melts into gooey bliss. Remove the foil and bake for an additional 5 minutes to get those tops perfectly golden and slightly crisp—a balance of soft and crunch that’s hard to resist.

Step 5: Make the Au Jus

While the sliders bake, melt butter in a saucepan over medium-high heat and sauté minced garlic for a minute to build aroma. Whisk in flour to create a roux, then gradually stir in beef broth and sauce until smooth. Let this simmer for 4 to 5 minutes until it thickens slightly, the perfect dipping companion that's bursting with beefy, savory flavor. Season to taste with salt and pepper.

How to Serve French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe

The image shows a step-by-step process of making a layered sandwich in a square yellow baking dish on a white marbled surface. The first layer is thin slices of pinkish cooked meat neatly spread out to cover the bottom. The second layer consists of smooth, overlapping slices of white cheese covering the meat fully. The third layer shows a woman's hand using a spoon to spread a generous amount of cooked caramelized onions on top of the cheese, adding texture and a brownish color. The final layer shows the same woman's hand spreading a creamy white sauce evenly over the onions, covering most of the surface. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

For a fresh touch, sprinkle a bit of finely chopped parsley over the sliders just before serving. It adds a lovely color contrast and a hint of brightness that balances the richness. You can also set out small ramekins of extra horseradish mayo or spicy mustard for guests to customize each bite.

Side Dishes

French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe pair beautifully with crispy fries or a fresh green salad. Opt for something crunchy or tangy to cut through the indulgence, like a peppery arugula salad with lemon vinaigrette or even some crunchy pickles on the side.

Creative Ways to Present

Try serving these sliders on a large wooden charcuterie board with small bowls of the au jus scattered around for dipping. Add a few toothpicks or miniature skewers to keep them intact and make for easy eating at parties. For a fun twist, you can also turn these sliders into handheld bites at your next gathering by cutting them into smaller portions.

Make Ahead and Storage

Storing Leftovers

Keep any leftover French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe in an airtight container in the refrigerator for up to 3 days. Separate the au jus in a different container to ensure the buns don’t become soggy overnight.

Freezing

If you want to freeze these sliders, assemble and bake them first, then wrap tightly in aluminum foil or plastic wrap and place them in a freezer-safe container. Freeze for up to 2 months. Thaw overnight in the refrigerator before reheating to retain their fresh-baked taste and texture.

Reheating

To reheat, cover the sliders loosely with foil and warm them in a 350-degree oven for about 10-15 minutes until heated through and the cheese is melty again. Warm the au jus separately on the stove to serve alongside your revitalized sliders for that perfect dip experience.

FAQs

Can I use a different type of cheese?

Absolutely! While provolone melts beautifully, Swiss or mozzarella also work well, adding their own unique flavor profiles to the French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe.

Is it okay to use pre-cooked roast beef slices?

Yes! Using thinly sliced roast beef from your deli is a huge time saver and still delivers the tender, juicy texture essential to this recipe.

Can I make the caramelized onions ahead of time?

Definitely. Caramelized onions can be prepared a day or two ahead and stored in the fridge. This allows you to streamline the assembly process when ready to bake.

What can I substitute for horseradish in the mayo spread?

If horseradish isn’t your thing, you can substitute with a bit of Dijon mustard or a splash of hot sauce to keep the spread creamy with a slight kick.

How thick should the au jus be?

The au jus should be lightly thickened, enough to coat the back of a spoon but still pourable for easy dipping. Adjust with a little more broth or flour to get the perfect consistency.

Final Thoughts

There is something incredibly satisfying about taking a classic favorite and turning it into a handheld treat like these French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe. These sliders are a delicious way to enjoy all that rich, savory flavor combined with soft bread and melty cheese. Whether you’re planning a party or a cozy night in, I urge you to give this recipe a try—you might just find yourself making it again and again!

French Beef Dip Sliders with Caramelized Onions and Au Jus Recipe

Ingredients You'll Need