In a small bowl, combine the salt, pepper, paprika, and garlic powder for seasoning, and set aside.
In a large skillet, heat 1 teaspoon of oil and 1 teaspoon of butter over medium-high heat. Season with half of the seasoning blend.
Add the beef to the hot pan and saute until almost fully cooked.
Remove the meat from the pan and add another tsp of oil and butter. Add the sliced peppers, onions, and mushrooms to the pan. Cook over medium heat until tender, but not so soft that it becomes mushy.
Add the meat back to the pan and season with the remaining mixture.
Slice the Hawaiian rolls lengthwise and add the bottom buns to a casserole dish. Spread the mayo on the bottom half of the sliders.
Spread the meat and veggie mix on the bottom buns and top with sliced cheese.
Add the top buns onto the sliders.
In a small bowl, mix together the butter spread ingredients. Brush the top of the rolls with the seasoned butter.
Cover with foil and bake at 375°F for 15 minutes. Uncover the dish and bake for an additional 5 minutes.
Cut the sliders into individual pieces, serve, and enjoy!