By KBC Associate 
Burger Seasoning: This is the one I’ve been using! (affiliate link) But there are many options we’ve tried from the grocery store and they’ve honestly all been pretty good. Hard to go wrong. If you don’t have a burger seasoning and want to use just salt and pepper, I would use 3/4 teaspoon of kosher salt per side on the beef.
About the beef: The goal is juicy, medium-big chunks with a nice golden brown crust. Using a very high heat to get the sear helps do this quickly so the beef doesn’t get dried out. I will even pull the beef off the heat when the insides are still a little pink, if I’ve gotten that nice crust on the outside. Kind of the same way you would do for a regular burger.
About the pan: You can use a different type of pan; the reason I recommend cast iron is because it gets very hot and will be easiest to give you that nice sear. But I’ve also made the beef in a nonstick pan and it still does okay! Not a big deal if you don’t have a cast iron.