Oil-Poached Tuna Salad

Preparation

1. Step 1

   Bring flageolet beans and 4 cups water to a boil in a large saucepan, reduce heat, and simmer until beans are tender, 50-60 minutes; season with salt. Let beans cool; drain. Transfer to a medium bowl. (Do not cook canned beans.)

   Step 2

   Cook green beans in another large saucepan of boiling salted water until crisp-tender, about 5 minutes. Drain and transfer to a colander set in a bowl of ice water. Let cool; drain and set aside. Wipe saucepan dry.

   Step 3

   Heat oil, rosemary, and garlic in same saucepan over medium-low heat until deep-fry thermometer registers 160°F. Season tuna with salt and pepper and cook in oil until opaque except for a bit of pink in the center, about 4 minutes per side. Using a slotted spatula, transfer tuna to a plate. Let poaching oil cool, then remove rosemary and garlic. Set aside 1/4 cup oil.

   Step 4

   Whisk anchovies, shallot, parsley, lemon juice, mustard, chopped dill, and reserved poaching oil in a small bowl; season with salt, pepper, and more lemon juice, if desired. Add some vinaigrette to bowl with flageolet beans and toss to coat.

   Step 5

   Break tuna into large pieces and arrange on a platter with flageolet and green beans, tomatoes, and olives. Top with a few dill sprigs and serve with remaining vinaigrette alongside.

   Step 6

   DO AHEAD: Tuna can be made 1 day ahead. Return fish to cooled oil, cover, and chill. Serve at room temperature.