It all started at the Super H Mart the other day. I bought a giant loaf of Barbari Bread. I wasn't sure what kind of bread it was, but I had bought a similar loaf from a European Bakery and made Reuben's.
I cooked the meat, onions and peppers in my Dutch Oven. Start by slicing the onions and peppers and cooking them in the pan with a little bit of garlic infused canola oil. Once they were soft and cooked, I put them in a separate bowl for later. Cut the steak into strips and use the same pan to cook the meat. I put just a little more oil in the pan and cooked the meat until no longer pink. I added another sliced onion to the pan with the steak and cooked until done. Add the peppers and onions back to the pan with the steak, mix together, put the lid on the pan and turn off the heat. This is letting the meat rest and holding in all the moisture of the meat and veggies.
In a separate pan, I heated some oil and cooked sliced mushrooms separate from the onions and peppers to have as a topping for the sandwiches. Dad doesn't really like mushrooms, so that is optional if you don't want to cook them together with the onions and peppers.
I had pre-heated the oven to 350 degrees to get the bread nice and toasty. Slice the bread to make 5 or 6 LARGE sandwiches. I used sliced Pepper Jack cheese for the bottom of the bun and shredded Sharp Cheddar cheese for the top of the bun and toasted in the oven for 8-10 minutes.
When the bread was toasted, it was time to pile the steak high on the bun and serve!