Sliders are such a great dish for a crowd, but they can be time-consuming to make on the stovetop or on a grill. After all, wouldn't you rather be hanging with your guests instead of flipping dozens of tiny burgers?
Luckily, there's actually a way that you can serve up sliders without having to spend tons of time at the stove -- you can bake them off as a casserole. Adding onion and butter directly to the burgers keeps them nice and moist while they bake. You can even do some of the prep for this casserole in advance, by preparing the mini burgers ahead of time. All you need to do is bake them off when it's time to eat. Be sure to serve ramekins of ketchup and mustard on the side for dipping.