Open-Faced Beef Sandwiches with Greens and Horseradish Cream

Ingredients

• Horseradish cream:
• 2 1/2 tablespoons drained prepared horseradish
• 2 tablespoons light sour cream
• 2 tablespoons crème fraîche
• Sandwich:
• Cooking spray
• 3 1/2 cups vertically sliced onion (about 2 large)
• 1/2 teaspoon kosher salt, divided
• 1 (1-pound) flank steak, trimmed
• 1/4 teaspoon freshly ground black pepper
• 2 cups trimmed arugula
• 2 teaspoons extra-virgin olive oil
• 1 teaspoon balsamic vinegar
• 4 (1 1/2-ounce) slices Texas toast, lightly toasted

Preparation

1. 1. To prepare cream, combine horseradish, sour cream, and crème fraîche in a small bowl; cover and chill.
2. 2. Preheat broiler.
3. 3. To prepare sandwich, heat a large nonstick skillet over medium heat. Coat pan with cooking spray. Add onion and 1/8 teaspoon salt to pan; cover and cook 10 minutes, stirring frequently. Uncover and cook 10 minutes or until onion is golden brown.
4. 4. Sprinkle steak with 1/8 teaspoon salt and pepper. Place steak on a broiler pan coated with cooking spray; broil 5 minutes on each side or until desired degree of doneness. Let stand 5 minutes. Cut steak diagonally across the grain into thin slices. Combine steak and remaining 1/4 teaspoon salt in a bowl, and toss to coat.
5. 5. Combine arugula, oil, and vinegar in a medium bowl; toss gently. Spread 2 tablespoons horseradish cream over each bread slice; top each with about 1/3 cup onion, 1/2 cup arugula mixture, and 3 ounces of steak.