Flat Iron Steak Sandwiches with Pickle Butter

Flat Iron Steak Sandwiches with Pickle Butter

Why does the idea of a knob of sweetly melting butter on top of a juicy steak seem so decadent to me? They are two products from the same animal, after all. It is a little indulgent, and it’s one of the most delicious combinations I can think of.

I eat it infrequently, but when I’m craving grilled meat I need a steak. The flat iron is one of my favorite cuts;  it’s way more affordable than my top pick, a rib-eye, and it comes from the beef chuck so it has great flavor. It’s also a nicely uniform size, which makes it perfect for slicing and piling into a sandwich.

I made a compound butter for this sandwich to fancy it up a little. The flavor reminds me of a classic Steak Béarnaise sauce, with lemon juice and pickles supplying the familiar tang along with some fresh tarragon.

Flat Iron steak sandwiches

Flat Iron Steak Sandwiches with Pickle Butter

Serving Size: makes 4 sandwiches


  • ¼ cup softened butter
  • 1/3 cup cornichon or baby gherkin pickles, chopped
  • 2 tablespoons chopped fresh tarragon
  • 1 teaspoon fresh lemon juice
  • Pinch sea salt, or to taste
  • 2 flat iron steaks, about 8 ounces each
  • Freshly ground black pepper
  • 1 small head bibb lettuce
  • 1/3 cup thinly sliced red onion
  • 4 crusty French sandwich rolls


  1. Prepare a charcoal grill for direct grilling or light a gas grill to medium-high.
  2. Mix together the butter, pickles, tarragon, lemon juice and salt to taste in a small bowl.
  3. Season the steaks generously with salt and pepper. Grill the steaks about 3 minutes per side for medium rare, or until done to your liking. Set aside to rest for 5 minutes.
  4. Lay the rolls on the outer edge of the grill to warm.
  5. To serve, line the rolls with lettuce leaves. Cut the steaks into ¼-inch thick slices and layer into the rolls. Top each sandwich with some onion and a few dollops of the pickle butter.


  1. That looks outrageously good Karen!

  2. This sounds appallingly delicious.

  3. Pickle butter? Genius! Can’t wait to give this recipe a try!

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