Pan-Seared Flank Steak with Mustard Sauce

Pan-Seared Flank Steak with Mustard Caper Sauce on cutting board

Pan-Seared Flank Steak with Mustard Sauce

This might just be the easiest flank steak recipe ever, with a quick cook time and no lengthy marinating required! The Dijon mustard sauce is good enough to slurp up on its own, but it's technically intended for spooning over the steak ...

Course Main Course

Cuisine Mediterranean

Keyword pan seared flank steak, steak with mustard sauce

Prep Time 10

Cook Time 15

Total Time 25

Servings

Calories 390kcal

Ingredients

Steak

1 ½ pound flank steak
½ teaspoon kosher salt
½ teaspoon freshly ground black pepper
1 tablespoon butter
1 tablespoon extra virgin olive oil

Dijon Mustard Sauce

3 tablespoons butter
1 tablespoon minced shallot
3 tablespoons dry vermouth or dry white wine
1 tablespoon Dijon mustard
½ teaspoon Worcestershire sauce
2 tablespoons capers, drained
1 ½ tablespoons chopped fresh tarragon

Instructions

Sear the flank steak. Season the 1 ½ pound flank steak with ½ teaspoon kosher salt and ½ teaspoon freshly ground black pepper. Melt 1 tablespoon of the butter with 1 tablespoon olive oil in a heavy-bottomed skillet over medium-high heat. Place the flank steak in the pan and cook, uncovered, until the meat is browned on both sides but still pink in the center, 5-6 minutes total. Transfer the meat to a cutting board and cover with foil to keep warm.
Make the mustard sauce. In the same pan over low heat, melt the remaining 3 tablespoons of butter with the pan drippings. Add 1 tablepoon minced shallot, stir, and cook for 30 seconds or until fragrant. Whisk in 3 tablespoons vermouth or dry white wine, 1 tablespoon Dijon mustard, ½ teaspoon Worcestershire sauce, 2 tablespoons capers, and 1 ½ tablespoons chopped fresh tarragon. Cook for 2-3 minutes.
Slice and serve. Slice the flank steak across the grain into thin slices. Spoon the sauce over the meat and sprinkle with more fresh tarragon if desired.

Notes

Storage: Store the steak and mustard sauce separately and refrigerate for up to 4 days. I suggest gently reheating the steak on the stove for best results. You can also use leftovers to make steak sandwiches, salads, and more.

Nutrition