Preparation

• Preheat the broiler. Remove the rolls from the packaging in one piece. Using a serrated knife, cut crosswise through all of the rolls at once to divide the top half from the bottom. Place both halves cut-side up on a sheet tray and broil for 2 minutes until lightly toasted.
• In a large skillet, heat the vegetable oil over medium heat. Add the onion and cook until just slightly softened, about 3 minutes. Add the ground sirloin and cook, breaking up into small pieces. Increase the heat to medium-high. Add the Worcestershire sauce, salt, and pepper, and stir well to combine. Cook until the beef is no longer pink and the liquid from the pan has almost fully evaporated, about 8 minutes. Remove from the heat.
• Preheat the oven to 375°F. In a small bowl, combine the mayonnaise, ketchup, and mustard.
• Spread the cut sides of the rolls with the mayonnaise mixture, then sprinkle with half of the cheese in an even layer. Layer the meat mixture over the cheese, then top with the remaining cheese and the pickles. Cover with the top half of the rolls.
• Brush the tops of the rolls all over with the olive oil and sprinkle with the everything bagel seasoning. Bake until the cheese is melty and the tops of the rolls are golden and toasted, about 10 to 12 minutes. Pull sliders apart and serve warm.