Split the dinner rolls and place the bottoms on a foil lined baking sheet.
Spread Miracle Whip on the cut side of the bottom half of the rolls. Layer a slice of ham, cheese and salami on top of the Miracle Whip. Spread the cut side of the top half of the rolls with mayonnaise. Replace the top half of the roll.
In a small bowl mix the melted butter, mustard, minced onion, and Worcestershire sauce. Brush evenly over the tops and sides of the slider rolls.
Cover the pan loosely with foil, and place on the center rack of the preheated oven for 15-20 minutes, until the cheese is melted and the sliders are heated thru.