For the Marinade
- 1 lb sirloin steak
- 2 tablespoons balsamic vinegar
- 1 tablespoon Worcestershire sauce
- 1/4 cup extra virgin olive oil
- 1/2 teaspoon dijon mustard
- 1/4 teaspoon garlic powder
- 1/2 teaspoon coarse salt
- 1/4 teaspoon ground black pepper
For the Mustard Sauce
- 2 teaspoons dijon mustard
- 1 teaspoon whole grain mustard
- 1 teaspoon mayonnaise
- 1/4 teaspoon horseradish
For the Gremolata
- 2 tablespoons basil leaves, minced
- 2 tablespoons parsley, minced
- 1 clove garlic, minced
- 1 tablespoon lemon zest
For the Sandwiches
- 1 french baguette, cut in half and sliced lengthwise
- 1 1/2 – 2 cups, baby arugula, depending on preference
- 1 heirloom tomato, sliced
- 1/4–1/2 cup crumbled blue cheese, depending on preference
- Drizzle of olive oil
- Marinate the steak: In a medium size bowl, stir together ingredients for the marinade. Place steaks in a large ziplock bag. Pour marinade over the steaks, seal the bag, and shake to coat. Chill in the fridge for 30 minutes.
- Make the gremolata: Combine the basil, parsley, lemon zest, and garlic in a small bowl. Set aside.
- Make the Mustard Sauce: Mix the mustards, mayonnaise, and horseradish in a small bowl until smooth. Set aside.
- Heat up a grill. Alternatively, heat a grill pan over medium high heat.
- Remove the steak from the fridge. Place on the grill or grill pan. Grill both sides 4-5 minutes for rare to medium rare. Remove steak to a plate and let rest for five minutes. Slice thinly against the grain.
- While steak is resting, grill the baguette: Drizzle the inside baguette halves with a little olive oil. Place each half on the grill with the crust facing up and cook 2-3 minutes, until slightly toasted and char marks form.
- Assemble the sandwiches: Spread mustard sauce on grilled baguette halves (I spread the sauce on both top and bottom halves of my sandwich). Sprinkle bottom slice with half of the blue cheese. Layer with sliced tomato, arugula and sliced steak. Sprinkle with gremolata, the rest of the blue cheese and any remaining mustard sauce. Cover with top half. Serve immediately.