Barbecued Flat Iron shines in sandwiches and salads like this one!
Combine garlic, shallot, brown sugar, oil, fish sauce, soy sauce and pepper in large resealable freezer bag. Pierce steaks all over with fork. Add to bag, turning to coat; seal and refrigerate for 8 hours or up to 24 hours.
Discard marinade from meat; pat steaks dry with paper towel. Grill steaks in a closed preheated barbecue over medium-high heat (400°F/200°C) for 6 to 8 minutes for ¾ inch (2 cm) thick steaks, turning twice or more, or until a digital instant-read thermometer inserted sideways into centre of steak reads 145°F (63°C) for medium-rare doneness at the least. Transfer steak to cutting board and let rest for 5 minutes.
Meanwhile, cook vermicelli according to package instructions. Drain and place in shallow bowl or platter; top with lettuce, bean sprouts, mint, cucumber and tomato (if using). Combine water, lime juice, sugar, fish sauce and chile in a small bowl, stirring until sugar is dissolved. Splash sauce over salad and toss to combine.
Cut steaks across the grain into thin slices and serve with Noodle Salad; garnish with peanuts.
Tip: Marinades are all about building steak flavour and juiciness. Piercing steak all over with a fork is what helps tenderize the steak.