The Ultimate Steak Sandwich!

Season your ribeye on both sides with salt and pepper and let rest for 15 minutes. At the same time, slice the onion and mushrooms and add to a pan with 4 Tbsp of butter. Season with salt and pepper and cook low and slow to caramelize. Fire up the grill and cook the steaks until desired temp (I chose medium rare). As they cook and rest, mix the remaining butter, garlic, and chopped parsley together. Slice open your bread. Spread on the butter. Pile on the steak, onions, and cheese. Melt on the grill and top with some arugula.