This Recipe is part of the 5 Fresh Supper Salads simple summer entertaining Menu
Ingredients
1/4 cup balsamic vinegar
1 large shallot, minced
2 teaspoons dijon mustard
1/2 teaspoon sugar
Sea salt
10 tablespoons extra-virgin olive oil
2 small vidalia onions, thinly sliced
2 tablespoons black peppercorns
6 (2 pounds total weight) tuna steaks, each about 1 inch thick
8 cups arugula leaves, stems removed
1 large fennel bulb, cored and thinly sliced
2 green onions, green tops thinly sliced
Directions
1. In a small nonreactive bowl, whisk together the vinegar, shallot, mustard, sugar, and 1⁄4 teaspoon salt until the sugar dissolves. Slowly whisk in 7 tablespoons of the olive oil until well blended to make a vinaigrette. Taste and adjust the seasonings and set aside.
2. In a large nonstick frying pan over medium heat, warm 2 tablespoons of the olive oil. Add the sliced onions and 1 teaspoon salt and sauté until softened and browned, 10–12 minutes. Transfer to a plate and set aside. Wipe the pan clean and set aside.
3. Place the peppercorns in a resealable plastic bag and seal closed. Using a mallet or the bottom of a small, heavy pan, coarsely crack the peppercorns. Season each tuna steak on both sides with a little salt. Then, dividing them evenly, press the cracked peppercorns into one side of each tuna steak.
4. Return the frying pan to medium-high heat and add the remaining 1 tablespoon olive oil. When the oil is hot but not smoking, add the tuna, peppered side down. Sear, turning once, until lightly golden on the outside and still dark pink in the center, or rare, about 2 minutes on each side, or until cooked to your liking. Transfer to a platter, tent with aluminum foil, and let rest for 5 minutes.
5. In a large bowl, toss together the arugula, fennel, and 1/4 teaspoon salt. Whisk the vinaigrette to recombine, then drizzle about half of it over the arugula mixture and toss well. Taste and adjust the seasonings. Divide the dressed arugula mixture evenly among individual plates. Spoon the sautéed onions over the top, dividing them evenly. Thinly slice each tuna steak and arrange on top of the onions. Drizzle each salad with some of the remaining vinaigrette and sprinkle with the green onion tops. Serve right away.
Serves 6

Reprinted with permission from Williams-Sonoma New Flavors for Salads. Recipe by Dina Cheney; photograph by Kate Sears. Copyright 2009 by Weldon Owen Inc. and Williams-Sonoma, Inc.
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