Preheat the oven to 350°F (175°C) and lightly spray a baking dish with nonstick cooking spray.

In a skillet over medium heat, melt 2 tablespoons of butter. Sauté onions and bell peppers until golden brown (5-7 minutes).

Add ribeye steak to the skillet, season with salt and pepper, and cook until no longer pink (3-4 minutes).

Place the bottom halves of slider buns in the baking dish. Spoon the steak mixture onto each bun and top with provolone cheese. Cover with the top halves of the buns.

Melt remaining butter and brush it over the tops of the sliders. Bake for 15-20 minutes or until golden brown and melty.

Let cool slightly before serving.