French Dip Sandwich

5 from 2 votes

A toasted French Dip Sandwich with melted Gruyère and a delicious homemade Au Jus is easy to make with leftover prime rib roast or deli meat!

Prep Time5

Cook Time10

Total Time15

Course: Main Course

Cuisine: American

Servings: servings

2 French sandwich rolls split
2 tablespoons butter softened
1 pound roast beef leftover prime rib or sirloin roast or from deli, thinly sliced
4 ounces Gruyere grated

Make Au Jus: Add 2 tablespoons butter (or beef drippings, if using) to saucepan and heat over medium-high heat. Add 1 teaspoon all-purpose flour and stir with a whisk to combine. Allow to cook for several minutes to slightly brown the flour. Pour 1/4 cup red wine into pan, whisk to combine, and allow to cook for 1-2 minutes to allow the alcohol to burn off. Add remaining ingredients (1 cups beef broth, 1 teaspoon Worcestershire sauce, 1 teaspoon spicy brown mustard, 1/4 teaspoon salt , and freshly ground pepper) to the pan, stir to combine, and bring to a gentle simmer.
Warm meat in Au Jus: Turn heat under Au Jus to low. Just prior to making the sandwiches, add the sliced 1 pound roast beef meat to the Au Jus. The goal is to warm the meat and allow it to soak up all the flavor, but not to overly cook it.
Prepare sandwiches: Preheat broiler to 500°F. Set open 2 French sandwich rolls on baking sheet and spread 2 tablespoons butter across surface. Broil until butter melts and edges of bread begin to brown, then remove from oven. Using tongs, remove meat from Au Jus, shake off any excess liquid, and place on rolls. Cover with shredded 4 ounces Gruyere. Broil for about 5 minutes, or just until cheese has melted.
Serve: Transfer Au Jus to a dish with enough headroom to allow for dipping. Slice sandwiches in half and serve warm. To enjoy, dip each bite into Au Jus.

If excess fat from drippings or butter remains on the top of Au Jus, a Gravy Fat Separator can be used, if desired.

Nutritional information is based on one half of a sandwich along with Au Jus.