These Hot Ham and Cheese Sliders bake for about 20 minutes in the oven covered with foil.  Depending on the thickness of your cheese slices, you may need to bake a little longer, until all the cheese is completely melted to ooey gooey splendor. After the cheese has melted, you can remove the foil and allow the sliders to bake a few more minutes to achieve those beautifully toasted golden-brown tops.