Prepare 4 sheets of foil and slice the hoagie rolls and set aside. Preheat oven to 250 degrees.

Heat a non-stick skillet with 1 Tbsp butter on medium high heat. Add mushrooms and half of the onions and cook 5-8 minutes or until mushrooms are browned and onions are cooked down. Remove and place on a plate.

Wipe the skillet with a paper towel and add 1/2 Tbsp of butter and return to the stove. Cook remaining onions and bell peppers for 5-8 minutes or until peppers start to brown and blister and the onions are cooked down. Add to a separate plate (unless everyone likes peppers/onions/mushrooms then add to the plate with mushrooms & onions).

Wipe the skillet again with a paper towel and add 1 Tbsp butter and return to stove again. Season half of the steak with salt & pepper and add to the skillet. Reduce to medium heat and cook for 2-4 minutes. Add in peppers & onions or half of the veggie mixture and cook for 1-2 minutes. Divide the meat & veggies in half as pictured above. Add 4 slices of cheese on top and allow the cheese to melt for 1-2 minutes.

Add the cooked meat & veggies and melted cheese to two hoagie rolls. Inside one sheet of foil, roll the hoagie roll tightly and place inside the oven for 10-15 minutes.

Repeat the process with the remaining steak & veggies or like I did with the mushrooms and onions - for the last two hoagie rolls. Serve fresh out of the oven with chips or your favorite French fries.