Dinner

French Dip Grilled Cheese with Caramelized Onions and Savory Au Jus Recipe

ByElla Hart January 24, 2026January 24, 2026

Introduction

French Dip Grilled Cheese combines tender roast beef and sweet caramelized onions with melted Swiss cheese and crisp French bread. Served with a flavorful homemade au jus for dipping, this sandwich is a warm, satisfying meal perfect for lunch or dinner.

Two thick grilled sandwiches stacked on a white plate on a white marbled surface, each sandwich showing three layers: the top layer is crispy golden-brown toasted bread with a crunchy texture, the middle layer has melted white cheese oozing out and tender thin slices of pink roast beef mixed with caramelized onions, while the bottom layer is another crispy toasted bread slice. On the side, there is a white cup filled with dark brown dipping sauce garnished with small green herbs. The scene is close-up, showing the juicy, melty, and textured details. photo taken with an iphone --ar 4:5 --v 7

Ingredients

8 slices crusty French bread
8 slices Swiss cheese
12 ounces thinly sliced roast beef
2 medium yellow onions, thinly sliced
4 tablespoons unsalted butter, plus extra for spreading
1 tablespoon olive oil
2 cups low-sodium beef broth
2 teaspoons Worcestershire sauce
1 teaspoon soy sauce
1 garlic clove, minced
1 sprig fresh thyme
Salt, to taste
Black pepper, to taste

Instructions

Step 1: In a large skillet over medium heat, melt 1 tablespoon butter with olive oil. Add the sliced onions and sauté, stirring frequently, until deeply caramelized and golden brown, about 12 to 15 minutes. Transfer onions to a plate and set aside.
Step 2: Wipe the skillet clean. In a small saucepan, combine beef broth, Worcestershire sauce, soy sauce, minced garlic, and thyme. Bring the mixture to a gentle simmer and cook for 5 minutes. Season with salt and pepper to taste. Strain through a small strainer and keep warm.
Step 3: Arrange 4 slices of French bread on your work surface. Layer each with a slice of Swiss cheese, a generous portion of roast beef, a scoop of caramelized onions, and a second slice of Swiss cheese. Top each with the remaining bread slices, pressing gently to secure.
Step 4: Spread unsalted butter evenly on the outside of each sandwich.
Step 5: Heat a clean skillet or griddle over medium heat. Grill the sandwiches for 3 to 4 minutes per side, pressing gently, until the bread is crisp and golden, and the cheese has melted.
Step 6: Slice the sandwiches in half and serve immediately with the warm au jus for dipping.

Tips & Variations

Use provolone or Gruyère cheese instead of Swiss for a different flavor.
Try roasted portobello mushrooms and vegetable broth to make a vegetarian version.
Let the cheese come to room temperature before assembling for better melting.
Spread a thin layer of horseradish cream or spicy mustard inside the bread for extra zing.
Use sturdy Italian bread or sourdough if French bread is unavailable.

Storage

Wrap leftover sandwiches tightly in foil and store in the refrigerator for up to two days. Reheat in a toaster oven or skillet to maintain a crisp crust. Store extra au jus in the refrigerator for up to three days and rewarm gently on the stove before serving.