French Dip Sandwiches

Ingredients

• 1 1/2 lb thinly sliced cooked roast beef
• 4 sturdy French rolls or hoagie rolls
• 8 slices provolone cheese
• 2 tbsp unsalted butter
• 1 small yellow onion, thinly sliced
• 2 cloves garlic, minced
• 3 cups low-sodium beef broth
• 1 tbsp Worcestershire sauce
• 1 tsp soy sauce
• 1/2 tsp dried thyme
• 1/4 tsp black pepper
• 1 tsp Dijon mustard, optional

Instructions

Follow each step in order. The directions below are written so a beginner can understand what to do, what to look for, and when to move on to the next step.

1. Step 1.Melt 1 tablespoon of butter in a saucepan over medium heat and add the sliced onion. Cook for 7 to 8 minutes until soft and lightly browned, stirring often so the edges caramelize without scorching.
2. Step 2.Add the minced garlic and cook for about 30 seconds, then pour in the beef broth. Stir in the Worcestershire sauce, soy sauce, thyme, black pepper, and optional Dijon mustard until the seasonings are evenly dispersed.
3. Step 3.Bring the broth to a gentle simmer and cook for 10 minutes so the onion and seasonings flavor the liquid. Taste before adding any salt, because beef broth, Worcestershire sauce, and soy sauce can already be quite salty.
4. Step 4.Lower the heat so the broth is steaming but not rapidly boiling, then add the sliced roast beef in small batches. Warm the meat for 1 to 2 minutes only; prolonged simmering can make thin roast beef dry and tough.
5. Step 5.Use tongs to transfer the warmed beef to a plate while leaving the seasoned broth in the saucepan. Strain the broth if you want a clear au jus, or leave the softened onions in for a more rustic dipping sauce.
6. Step 6.Split the rolls lengthwise while keeping a hinge if possible and spread the cut sides with the remaining butter. Toast them under a broiler or in a skillet until lightly golden, watching closely because bread can brown quickly.
7. Step 7.Divide the warm roast beef evenly among the bottom halves of the toasted rolls, arranging the slices loosely rather than compressing them. Spoon a few softened onions from the broth over the beef if desired.
8. Step 8.Lay two slices of provolone over each sandwich and place the open sandwiches under a broiler for 30 to 60 seconds. Remove them as soon as the cheese is melted and bubbling at the edges without burning the rolls.
9. Step 9.Close the sandwiches and cut each one in half for easier dipping. Ladle the hot au jus into individual small bowls so every serving has enough broth without requiring people to share a single dipping container.
10. Step 10.Serve immediately while the cheese is melted and the rolls retain some crispness. Dip briefly rather than soaking the sandwich for a long time, which gives the classic juicy bite without causing the bread to fall apart.