Ingredients
4 tbsp. butter, divided
1 large onion, thinly sliced
1 tsp. freshly chopped thyme
1 Italian loaf bread
1/2 lb. thinly sliced roast beef
10 slices provolone cheese
1/2 tsp. garlic powder
1 tbsp. butter
2 cloves garlic, minced
1 1/2 c. low-sodium beef broth
1 tbsp. Worcestershire sauce
1 tsp. freshly chopped thyme
Kosher salt
Freshly ground black pepper
Preparation
Step 1Make sandwiches: Preheat oven to 375°. In a large skillet over medium heat, melt 2 tablespoons butter. Add onion and thyme and cook, stirring occasionally, until caramelized, 15 minutes.Step 2Slice bread into ½" slices, making sure not to cut all the way through. Between every other slice, add a slice of roast beef, two slices of provolone, and caramelized onions. Step 3Melt remaining 2 tablespoons butter and add garlic powder. Brush butter all over loaf of bread and in between empty slices. Step 4Wrap in foil and place on a medium baking sheet. Bake until cheese is melty, 15 minutes. Step 5Meanwhile, make au jus: In a small saucepan over medium heat, melt butter. Add garlic and cook until fragrant, 1 minute. Add broth, Worcestershire, and thyme. Season with salt and pepper. Simmer until slightly reduced, 10 minutes. Step 6Serve sandwich loaf with au jus and let guests pull apart the sandwiches.
