From: Chef Jeff Orr, Cocoliquot, Madison, WI. Yield: 1 serving.
1 red onion, very thinly sliced
as needed, soybean oil or other neutral oil
to taste, salt and pepper
2 Tbsp. sherry vinegar
1 4- to 6-oz. hanger steak, split and trimmed
2 crusty sandwich rolls, such as ciabatta, split, buttered and toasted