How to Make It
Light a grill or preheat the broiler. In a saucepan of boiling salted water, cook the fregola until al dente, about 20 minutes. Drain and cool under running water; shake off the excess water.
Meanwhile, rub the steaks with the chile powder and season with salt and pepper. Grill the steaks and the onion slabs over high heat for about 8 minutes, turning occasionally, for medium-rare meat and tender onions. Let the skirt steaks rest for about 10 minutes. Let the onions cool slightly, then coarsely chop them.
In a large bowl, whisk the lemon juice into the olive oil and season with salt and pepper. Add the fennel, oranges, arugula, radishes, fregola and grilled onion and toss well. Thinly slice the skirt steaks across the grain and arrange on plates. Spoon the tapenade over the steaks, mound the salad alongside and serve.