- 3 tbsp unsalted butter for onions
- 1 medium onion thinly sliced
- 2 tsp fresh thyme minced
- ¼ tsp kosher salt
- ¼ tsp black pepper
- 12 sweet rolls like King’s Hawaiian
- 10 slices provolone cheese
- 14 oz sliced deli roast beef
- ½ cup unsalted butter melted (for topping)
- 1½ tbsp dried onion soup mix
- 1 packet au jus gravy mix
- 3 cups water for au jus
Optional: fresh chopped parsley for garnish