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