Prep time: 10 minutes
Total time: 2 1/2 hours (2 hours marination)
2 (1 pound|450 gram) pieces skirt steak
½ cup|125 ml fish sauce
¼ cup|60 ml fresh lime juice
¼ cup|65 grams granulated sugar
1 tablespoon chili flakes
kosher salt, to taste
2 bunches scallions, trimmed
1. In a large bowl, whisk together the fish sauce, lime juice, sugar, and chili flakes with ¼ cup|60 ml water. Add the steak and toss to coat. Cover and marinate for 2 hours.
2. Remove the steak from the marinade and let sit at room temperature. Light a grill. Season the steak with salt and rub it with a bit of oil. Drizzle the scallions with oil as well. Grill the steak, flipping once, until cooked to desired doneness. Grill the scallions, turning as needed, until charred, about 3 minutes. Transfer the steak to a cutting board and allow to rest for 10 minutes before slicing. Place the steak slices on a platter along with the scallions and sprinkle with the crispy onions.