How to Make It
Set the flank steak in a large, shallow glass or ceramic baking dish. Add the Kumquat">http://www.foodandwine.com/recipes/kumquat-green-peppercorn-and-garlic-p..., Green Peppercorn and Garlic Paste and rub it all over both sides of the flank steak. Cover the baking dish with plastic wrap and refrigerate the steak for at least 2 hours or overnight. Let the flank steak return to room temperature before grilling.
Light a grill or preheat the broiler and position the shelf 8 inches from the heat. Scrape the paste off the steak, if desired, then grill or broil it, turning once, until browned, about 12 minutes for medium rare. If the steak is cooked with the paste on, some of it may fall off when the steak is turned. Let the flank steak rest for 10 minutes.
In a large bowl, combine the olive oil with the orange juice. Season with salt and pepper and then whisk until the salt dissolves. Add the arugula, kumquats and red onion and toss well, then transfer the salad to dinner plates.
Using a sharp knife, thinly slice the flank steak on the diagonal across the grain. Arrange the slices on the salads. Garnish the plates with the cilantro leaves and serve the steak immediately.