Preheat oven to 350 degrees.
Slice onion and bell pepper.
Heat up a large skillet on medium-high heat. Add frozen chipped steak. As the meat cooks, user a spatula to chop up the meat. Remove the steak from the pan.
Cook the onion and bell pepper on medium heat until tender. Add a little olive oil when cooking if necessary. Remove from the heat and set aside.
Mix mayonnaise, lemon juice and minced garlic in a small bowl. Melt butter with the rest of the minced garlic and add chopped parsley.
Slice the slider rolls in half. When doing this, keep the rolls attached as one sheet. There should be a top sheet and a bottom sheet of rolls when sliced correctly. Place the bottom layer sheet of rolls into a large casserole dish. Spread the garlic aioli evenly on the bottom half of the rolls. Spread cooked steak evenly on top of the aioli.
On top of the steak, spread the sautéed onions and bell peppers. Add the slices of cheese evenly on top. Spread any extra garlic aioli on the top sheet of slider rolls before placing the sheet on top of the cheese. Spread the melted butter with garlic and parsley on the tops of the rolls.
Bake about 10-15 minutes or until the cheese melts and the buns become slightly golden brown.