Preheat oven to 400F (200C). In a small bowl, stir together softened butter, minced garlic, and chopped parsley. Spread evenly over cut sides of split French rolls. Place rolls cut-side up on a baking sheet and toast for 5 minutes until lightly golden and fragrant.

Melt 2 tablespoons butter in a medium saucepan over medium heat. Add minced shallot and garlic; saute for 2 minutes until soft and fragrant. Whisk in flour and cook for 1 minute.

Pour in red wine (if using) to deglaze pan, whisking up browned bits. Add beef bone broth, Worcestershire sauce, rosemary sprig, thyme sprigs, black pepper, and onion powder. Bring to a gentle boil, then simmer on low for 8 to 10 minutes until rich and aromatic. Discard herb sprigs.

Using tongs, gently submerge sliced roast beef in batches into hot simmering au jus for 30 to 45 seconds to warm through and absorb savory pan juices.

Using tongs, transfer warm juicy beef onto bottom halves of toasted rolls, piling generously. Layer 2 slices of provolone cheese over each sandwich.

Return open-faced sandwiches under oven broiler on HIGH for 2 to 3 minutes until cheese is completely melted, bubbly, and draping over beef.

Close sandwiches with toasted tops. Ladle hot au jus into individual small ceramic dipping bowls and garnish with chives. Serve piping hot with kettle chips and crisp pickles for dipping!