Cookwith - Herb-Marinated Flat Iron Steak Sandwiches with Dill, Chive, and Basil Aioli

Ingredients

• 1 lb flat iron steak
• 2 tbsp fresh dill, finely chopped (plus more for garnish)
• 2 tbsp fresh chives, finely chopped
• 2 tbsp fresh basil, finely chopped
• 3 garlic cloves, minced
• 1 tsp lemon zest
• 2 tbsp lemon juice
• 2 tbsp olive oil
• 1 tbsp Dijon mustard
• 1 tsp kosher salt
• 1/2 tsp black pepper
• 1/2 cup mayonnaise
• 1 tsp white wine vinegar
• 4 sandwich rolls or ciabatta buns, split
• 1 cup arugula or baby greens