3 tablespoons minced fresh tarragon or 1 tablespoon dried tarragon
1 teaspoon salt
3/4 teaspoon sugar
1/2 teaspoon ground mustard
1/2 teaspoon pepper
1/4 teaspoon garlic powder
1 large red onion, sliced and separated into rings
1/2 pound fresh mushrooms, sliced
1 large bunch romaine
1/2 cup minced fresh parsley
Broil steak 6 in. from the heat for 7 minutes on each side or until meat reaches desired doneness (for medium-rare, a thermometer should read 135°; medium, 140°; medium-well, 145°). Cool slightly. Cut steak into very thin strips.
In a large bowl, combine the oil, vinegar, tarragon, salt, sugar, mustard, pepper and garlic powder. Add the steak, onion and mushrooms; toss to coat. Cover and refrigerate for at least 4 hours.
Just before serving, place romaine on plates. Using a slotted spoon, arrange beef mixture over romaine. Garnish with parsley.