Flatiron Steak with Creamy Horseradish Sauce

Flatiron Steak with Creamy Horseradish Sauce
  • Prep Time
  • 4Servings


  • 3 tablespoons EVOO
  • 1 jar (6 oz.) prepared horseradish, drained
  • 2 tablespoons plus 2 tsp. spicy brown mustard
  • Salt and pepper
  • 4 flatiron steaks (6 to 8 oz. each)
  • 8 ounces sour cream
  • 2 pounds sweet potatoes, peeled and sliced crosswise 1/4 inch thick


In a large, shallow bowl or baking dish, whisk together 2 tbsp. EVOO, 1 tbsp. horseradish, 2 tsp. mustard and 1/4 tsp. salt. Add the steaks, turning to coat. Cover and refrigerate for at least 30 minutes or overnight.

In a small bowl, combine the sour cream, the remaining horseradish and mustard and 1/4 tsp. salt. Cover and refrigerate until ready to use.

Preheat a grill to medium; oil the grate. In a large bowl, toss the sweet potatoes with the remaining 1 tbsp. EVOO, salt and pepper. Grill the potatoes, turning once, until tender, about 10 minutes. Transfer to a plate and tent with foil to keep warm.

Increase the grill heat to medium-high. Add the steaks and grill, turning once, until medium-rare, about 5 minutes. Serve the steaks with the sweet potatoes and horseradish sauce on the side.