Steak with Horseradish-Chive Sauce

Preparation Time: 15 minutes
Start to finish: 36 minutes
Internet Address: http://www.foodnetwork.com/recipes/steak-with-horseradish-chive-sauce-recipe/index.html

1 pound hanger steak (center sinew removed)
1 cup red wine vinegar
1/3 cup cognac
1/2 cup olive oil
1 minced shallot
2 tablespoons chopped rosemary
4 chopped garlic cloves
2 tablespoons sugar
pepper to taste
salt to taste
1 bunch chives
1 cup sour cream
3 Tablespoons horseradish
salt to taste

Marinate a 1-pound hanger steak (center sinew removed) in a mix of 1 cup red wine vinegar, 1/3 cup cognac, 1/2 cup olive oil, 1 minced shallot, 2 tablespoons chopped rosemary, 4 chopped garlic cloves, 2 tablespoons sugar, and pepper to taste for up to 6 hours. Preheat a grill to medium-high on one side. Remove the steak from the marinade; pat dry and season with coarse sea salt and pepper. Sear over direct heat until marked, about 4 minutes per side. Transfer to the cooler side; cover and cook until the meat reaches 130 for medium-rare, about 10 minutes. Let rest 5 minutes before slicing. To make the sauce, blanch 1 bunch chives in simmering water for 3 minutes, then rinse under cold water and squeeze dry. Puree with 1 cup sour cream, 3 tablespoons horseradish and a pinch of salt.