• Turn your oven on and set it to 400°F. Let the oven heat up completely before putting the sandwiches inside. This helps the Texas toast get crispy instead of soft or soggy.
• Grab a baking sheet or sheet pan. You can line it with parchment paper or aluminum foil if you want easier cleanup, but this is optional.
• Take the frozen garlic Texas toast directly out of the freezer. Do not thaw it first. Place the slices flat on the baking sheet in a single layer, leaving a little space between each piece.
• Divide the cooked roast beef evenly between the pieces of Texas toast. Place the beef directly on top of the frozen bread. Spread it out so most of the bread is covered, but try not to pile the meat too high.
• Cut the provolone cheese slices in half so they fit well over the sandwiches. Then place 2 of the cut pieces (so one whole slice of provolone cheese) on top of the roast beef, on each sandwich. Make sure the cheese is sitting mostly over the meat so it melts down over the roast beef instead of dripping all over the pan.
• Carefully place the baking sheet into the preheated oven. Bake the sandwiches at 400°F for 12-15 minutes.
• Around the 12-minute mark, look at the sandwiches. The Texas toast should be golden brown and crispy around the edges, the roast beef should be hot, and the provolone cheese should be completely melted.
• If the bread is not crispy enough or the cheese has not fully melted, let the sandwiches bake for another 2-3 minutes. Keep an eye on them so the bread does not burn.
• Carefully take the baking sheet out of the oven. The pan will be very hot, so use oven mitts. Allow the sandwiches to sit on the baking sheet for about 1-2 minutes. This gives the cheese a chance to settle and keeps you from burning your mouth.

Au Jus Dipping Sauce

• Add the water, beef bouillon, Worcestershire sauce, garlic powder, onion powder, and black pepper to a small saucepan.
• Place the saucepan over medium-high heat. Stir the mixture until the bouillon is completely dissolved.
• Lower the heat and let it simmer for about 3-5 minutes. Stir in the butter, then taste the au jus before adding any salt because beef bouillon can already be salty.
• Pour into small bowls and serve warm alongside the roast beef sandwiches.