Preparation

• Set an oven rack about 6 inches away from the element and heat the broiler to high.
• Cut the flank steak crosswise (against the grain) at a very sharp angle (about 30 degrees) to form thin slices of beef between 1/8 and 1/4 inch thick and about 2-1/2 inches wide; you should have about 12 long slices of beef. Season the beef with 1/2 tsp. salt. Mix the hoisin sauce with the chili sauce and then brush on both sides of the beef. Sprinkle the carrots, red bell pepper, and scallions with 1/4 tsp. salt. Arrange the scallions and peppers in an alternating pattern down the length of each strip of beef. Sprinkle the carrots over the scallions and peppers. Roll the pieces of beef lengthwise into tight spirals and set them, seam side down, on a heavy baking sheet lined with aluminum foil. Brush the tops with some of the remaining hoisin sauce (you may not need all the sauce).
• Broil the beef until it starts to brown (but doesn’t burn) and is firm to the touch, 4 to 6 min. Turn off the broiler but let the beef sit in the oven for another 3 min. so the inside cooks through but is still slightly pink; you can check by slicing into one of the thicker rolls. To serve, insert two or three toothpicks evenly down the length of each roll. Slice between the toothpicks to get bite-size pieces.