Place the bulgur wheat in a bowl with 3 cups of water and a pinch of salt. Cover and let stand for 2 hours, until the bulgur absorbs most of the water and is tender. Drain off any remaining water in a colander and set the bulgur aside.

Place the fish on a platter or pan and sprinkle with salt, pepper, and lemon juice. Cover with plastic wrap and refrigerate until ready to use.

Heat two tablespoons of olive oil in a deep skillet or wide pot over medium heat and cook the leek and fennel until softened but still al dente, about 5 minutes. Stir in the garlic. Raise the heat a bit and add the tomatoes. Cook over high heat until they start to crinkle. Stir in the olives. Carefully pour in 2 tablespoons of the ouzo. When the alcohol steams off, turn off heat, add the walnuts, and drained bulgur and toss to combine. Stir in the lemon zest and herbs. Taste and adjust seasoning with salt and pepper.

In a separate large frying pan, heat two more tablespoons of olive oil over medium heat. Place the fish fillets skin side up and sauté for 3 minutes. Turn carefully with a spatula and cook on the other side. Turn up heat, pour in the remaining ouzo, and cook for another minute or two until the alcohol evaporates but there is still liquid left in the pan.

Remove the fillets. Toss the pan juices into the bulgur mixture and serve the bulgur in four equal portions on four dinner plates. Place a fillet over the bulgur mound. Drizzle remaining olive oil over each dish. Garnish with chopped dill and a lemon slice and serve.