Heat olive oil in a large skillet over medium-high heat. Add the sliced onion and bell pepper and cook until softened, about 5-7 minutes.
Add the thinly sliced ribeye steak to the skillet with the vegetables. Season with salt and pepper. Cook, stirring occasionally, until the steak is browned and cooked through.
Stir in the Cheez Whiz until melted and well combined with the steak and vegetables.
Slice the slider buns in half horizontally.
Place the bottom halves of the slider buns on a baking sheet. Spoon the cheesesteak mixture evenly over the buns.
Top each slider with slices of Provolone cheese.
Place the top halves of the slider buns over the cheese.
Broil for 1-2 minutes, or until the cheese is melted and bubbly and the buns are lightly toasted.
Serve immediately.
Notes
For an extra layer of flavor, you can add sautéed mushrooms to the filling. These are best served fresh but can be kept warm in a low oven for a short period.