Fried Anchovies with Lemon Yogurt Sauce

Steps

1. Clean the anchovies: pinch the head between your thumb and index finger, bend it down toward the belly, and pull gently; the innards come out with it. Run your thumb along the open belly to finish cleaning it. For butterflied anchovies, open the belly all the way to the tail, lay the fish flat skin side up, press along the backbone, then flip it and lift out the spine in one piece, snapping it off at the tail.
2. Rinse the anchovies quickly in a bowl of ice water without letting them soak. Drain, spread them on a clean kitchen towel or paper towels, pat them completely dry, and refrigerate until it's time to fry.
3. Make the sauce. Finely grate the zest of one lemon and squeeze half of it to get 1 tablespoon of juice. Grate the garlic. Chop the dill, saving a few fronds for garnish. Mix the yogurt with the zest, juice, garlic, chopped dill, 1 tablespoon of the olive oil, and 2 pinches of salt. Cover and chill for at least 15 minutes, so the garlic and dill can flavor the yogurt.
4. Halve the cherry tomatoes, cut the cucumber into 1/4 inch (5 mm) half-moons, and drain the olives. Keep them chilled with the arugula, undressed. Cut the remaining lemon half and the second lemon into wedges.
5. Pour the sunflower oil into a deep saucepan or wok to a depth of about 1 1/2 inches (4 cm), without filling it more than halfway. Heat it over medium-high to 350°F (180°C) on a thermometer. Set a wire rack over a sheet pan lined with paper towels next to the stove.
6. Right before frying, season the anchovies lightly with 1/4 teaspoon of the fine salt. Pour the semolina into a large bowl, add a third of the anchovies, and toss them by hand to coat well. Transfer them to a colander and shake off the excess: only a thin, sandy coating should remain.
7. Drop the coated anchovies into the oil one by one or in small, spread-out handfuls so they don't stick together. Fry for 1 1/2 to 2 minutes, separating them with a slotted spoon: they're done when they turn light golden and the sizzling clearly quiets down. Lift them out with a spider, set them on the rack, and salt them right away with a pinch of fine salt. Let the oil come back to 350°F (180°C), then coat and fry the other two thirds the same way.
8. While the oil reheats, dress the salad: toss the arugula, tomatoes, cucumber, and olives with 2 tablespoons of the olive oil, a pinch of salt, and the juice of one lemon wedge.
9. Plate in a stoneware dish: the salad on one side, the fried anchovies piled next to it, the bowl of yogurt sauce topped with the dill fronds, and the remaining lemon wedges. Serve immediately; the anchovies lose their crunch within 10 minutes.