French Onion French Dip Sandwiches Recipe

Introduction

French Onion French Dip Sandwiches combine the rich, caramelized flavors of French onion soup with tender roast beef and melted Gruyere cheese in a crusty baguette. This comforting sandwich is perfect for a cozy meal and comes with a savory au jus for dipping that elevates every bite.

Ingredients

• 1 long French baguette
• 1 and 1/2 pounds (340g) rare roast beef, thinly sliced
• 3 tablespoons (42g) unsalted butter
• 1 teaspoon fresh thyme leaves, finely chopped
• 3 large yellow onions, peeled and thinly sliced
• 1/2 teaspoon salt
• 1/2 teaspoon black pepper
• 1/4 teaspoon red pepper flakes
• 1/2 cup (113ml) cooking sherry
• 2 cups (454ml) beef stock
• 1/2 teaspoon cornstarch
• 1 teaspoon water
• 10 ounces Gruyere cheese, grated

Instructions

1. Step 1: Slice the baguette into 4 pieces. Then slice each piece in half, cutting only three-quarters of the way through, so the sandwich holds together.
2. Step 2: Preheat your oven to 500°F (260°C).
3. Step 3: Evenly divide the roast beef among the bread pieces, filling each with a quarter of the beef. Place each assembled sandwich on a piece of aluminum foil and set aside.
4. Step 4: In a large skillet, melt the butter over medium heat. Add the thyme and onions, stirring well to coat. Cook, stirring occasionally, for 20 to 25 minutes until the onions are soft and golden.
5. Step 5: Add the salt, black pepper, and red pepper flakes to the skillet and stir. Cook for 2 minutes, then stir in the cooking sherry. Continue cooking for 3 to 4 minutes until the onions absorb the sherry.
6. Step 6: Pour in the beef stock and increase the heat to medium-high to bring to a boil. Reduce heat to a simmer and cook for 5 minutes.
7. Step 7: Mix cornstarch with water to make a slurry, then add it to the onion mixture. Cook for 1 to 2 minutes until the au jus slightly thickens.
8. Step 8: Keeping the heat on low, use a slotted spoon to remove the onions from the broth and place them in a large serving bowl. Pour the remaining au jus into individual ramekins for dipping.
9. Step 9: Layer the sandwiches by placing grated Gruyere cheese first, then the caramelized onions on top of the roast beef.
10. Step 10: Wrap each sandwich tightly in the aluminum foil. Place the wrapped sandwiches on a baking sheet and bake in the oven for 5 minutes, until the cheese melts.
11. Step 11: Carefully remove the sandwiches from the oven, unwrap, and serve immediately with the warm au jus on the side for dipping.

Tips & Variations

• For extra richness, add a slice of provolone or mozzarella cheese along with Gruyere.
• Use caramelized onions leftover from French onion soup to save time.
• Substitute cooking sherry with dry white wine or apple cider vinegar for a different flavor.
• Try adding sautéed mushrooms to the onion mixture for extra earthiness.

Storage

Store any leftover sandwiches separately from the au jus in airtight containers in the refrigerator for up to 2 days. Reheat sandwiches wrapped in foil in a 350°F (175°C) oven until warmed through. Reheat the au jus gently on the stovetop or in the microwave before serving.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use other types of bread for this sandwich?

Yes, you can use other crusty breads like ciabatta or sourdough, but a French baguette works best to hold the fillings and soak up the au jus.

Is it necessary to use cooking sherry in the au jus?

Cooking sherry adds a subtle sweetness and depth, but you can substitute with dry white wine, cider vinegar, or simply omit it if preferred.

French Onion French Dip Sandwiches Recipe

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★★★★★

4.6 from 64 reviews

• Author: Lila
• Total Time: 55 minutes
• Yield: 4 servings 1x

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Description

These French Onion French Dip Sandwiches combine tender roast beef with caramelized onions and melted Gruyere cheese on a crusty French baguette. Served with a rich, flavorful au jus for dipping, this comforting sandwich elevates your mealtime with deliciously savory, aromatic components and a perfect balance of textures.

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Ingredients

Scale 1x2x3x

Sandwich

• 1 long French baguette
• 1 and 1/2 pounds (340g) rare roast beef, thinly sliced
• 10 ounces Gruyere cheese, grated

Onions and Au Jus

• 3 Tablespoons (42g) unsalted butter
• 1 teaspoon fresh thyme leaves, finely chopped
• 3 large yellow onions, peeled and thinly sliced
• 1/2 teaspoon salt
• 1/2 teaspoon black pepper
• 1/4 teaspoon red pepper flakes
• 1/2 cup (113ml) cooking sherry
• 2 cups (454ml) beef stock
• 1/2 teaspoon cornstarch
• 1 teaspoon water

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Instructions

1. Prepare the bread: Slice the baguette into 4 equal pieces. Then slice each piece in half lengthwise, cutting only about 3/4 of the way through to keep the halves connected.
2. Preheat the oven: Set your oven to 500 degrees Fahrenheit to get it ready for toasting the sandwiches later.
3. Assemble the sandwiches: Evenly divide the thinly sliced rare roast beef among the baguette pieces, filling each with about 1/4 of the meat. Place each prepared baguette on a piece of aluminum foil and set aside.
4. Cook the onions: In a large skillet, melt the butter over medium heat. Add the chopped thyme and sliced onions, stirring well to coat. Cook the onions, stirring occasionally, for 20 to 25 minutes until they are soft and golden brown.
5. Season and deglaze: Stir in salt, black pepper, and crushed red pepper flakes. Cook for 2 minutes, then add the cooking sherry. Continue cooking for 3 to 4 minutes, stirring occasionally, allowing the onions to absorb the sherry’s flavor.
6. Add beef stock and simmer: Pour in the beef stock and increase the heat to medium-high until the mixture boils. Lower the heat to a simmer and continue cooking for 5 minutes to develop the au jus.
7. Thicken the au jus: Mix the cornstarch with a teaspoon of water to create a slurry. Add this to the onion mixture and cook for another 1-2 minutes to slightly thicken the liquid.
8. Separate onions and au jus: Keep the heat at simmer. Using a slotted spoon, remove the onions from the broth and place them in a large serving bowl. Pour the remaining au jus into individual ramekins for dipping.
9. Top sandwiches: Evenly distribute the grated Gruyere cheese over the roast beef on each sandwich, then top with the caramelized onions.
10. Wrap and bake: Wrap each sandwich tightly in the aluminum foil. Place wrapped sandwiches on a baking sheet and bake in the preheated oven for 5 minutes to melt the cheese.
11. Serve: Carefully remove the sandwiches from the oven, unwrap the foil, and serve immediately. Accompany with the individual ramekins of au jus for dipping the sandwiches.

Notes

• Cutting the baguette 3/4 through helps keep the sandwiches intact while allowing them to open up for fillings.
• Low and slow cooking of the onions is essential for deep caramelization and rich flavor.
• Cooking sherry adds sweetness and complexity but can be substituted with dry white wine if unavailable.
• The cornstarch slurry slightly thickens the au jus without overpowering its savoriness.
• Using Gruyere cheese adds a nutty, creamy element that melts beautifully over the beef and onions.
• Serve these sandwiches fresh and warm for the best texture and flavor.

• Prep Time: 15 minutes
• Cook Time: 40 minutes
• Category: Sandwiches
• Method: Baking
• Cuisine: French-American

Keywords: French dip sandwich, caramelized onions, roast beef sandwich, au jus, Gruyere cheese sandwich, French baguette, comfort food