Follow the steps in order for the best result.
Begin by manually shredding any leftover cooked beef. Set aside.
Finely dice the garlic, onion, and both bell peppers. Keep them separate for now.
Heat a skillet over medium heat. Add the vegetable oil and allow it to get hot.
Add the minced garlic to the hot oil and cook for approximately 30 seconds, until fragrant.
Introduce the shredded beef to the skillet and heat it thoroughly.
Reduce the heat to low and pour in the barbecue sauce, ensuring that the beef is well coated. You can adjust the amount of sauce to your preference. Allow the mixture to simmer gently on low heat.
In a separate pan, sauté the diced onions and peppers until they become soft and translucent.
Assemble the sandwiches: Slice open the ciabatta rolls. On one half of each roll, layer slices of Monterey Jack pepper cheese and toast in the oven until the cheese is melted and bubbly. Place the shredded beef mixture on the other half of each roll. Top with the sautéed onions and peppers.
Serve the sandwiches warm, with extra sauce and cheese available for those who desire it. Enjoy!