In a small mixing bowl, combine cream cheese, horseradish, garlic powder, salt, and pepper until smooth.

Spread approximately 1 ounce of the cream cheese mixture evenly over each flour tortilla.

Layer two slices of provolone cheese and 2 ounces of roast beef over the cream cheese on each tortilla.

Roll each tortilla tightly into a cylinder and wrap in plastic film; refrigerate for 15 minutes to ensure structural integrity during slicing.

In a small saucepan, combine beef broth, Worcestershire sauce, onion powder, and butter.

Bring the liquid to a simmer over medium heat and maintain for 8 minutes to concentrate flavors for the au jus.

Remove tortillas from refrigeration, discard plastic film, and slice into 1-inch wide rounds.

Arrange on a platter and serve with the warm au jus in a ramekin for dipping.