Steak Sandwich - cooking recipe

Ingredients

3 tablespoons unsalted butter
1 tablespoon olive oil, plus
1 teaspoon olive oil
1/2 red onion, thinly sliced
1/2 yellow onion, thinly sliced
salt
fresh ground black pepper
1 tablespoon crumbled blue cheese
1/2 teaspoon Dijon mustard
2 (3 ounce) rib eye steaks
2 ciabatta or 2 other sturdy sandwich buns (don't use hamburger buns, good sturdy bread is best)

Preparation

Heat one tablespoon of the butter and one tablespoon of the oil over medium and add both types of onion and a little salt and freshly ground black pepper; cook, stirring, until crispy and brown, about 15 minutes, then set aside.
Mash together the remaining 2 tablespoons butter, the cheese and mustard and set aside.
Rub the steaks with salt and pepper; heat the remaining 1 teaspoon olive oil in a medium cast-iron skillet over high heat; when very hot, add both the steaks and cook without disturbing for 2 minutes; flip and brown the other side for 2 more minutes- this will give you medium doneness but still pink meat.
Place the steaks onto the roll bottoms, top each with half the butter mixture and then smother with onions; top with the roll tops and eat with ice cold, alcoholic beverages on a Friday evening.