Preheat the oven to 445°F.

In a large rimmed baking dish, combine the eggplant, onion, and artichoke hearts with a glug of olive oil and a sprinkle of salt. Toss until fully coated, and then shake the pan to make sure the vegetables lie flat and have the maximum possible surface area exposed. Roast in the oven for 20 minutes. With a spatula, redistribute the vegetables so they brown on the opposite side, and return to the oven for another 10-20 minutes, until the vegetables are dark brown and caramelized. In the meantime, make the salsa verde: Combine the capers, herbs, anchovy paste, lemon juice, oil and salt in a small bowl and whisk until fully incorporated.

Coat a large skillet with olive oil and set it over high heat. Pat the fish fillet dry and when the pan starts to smoke, set it flesh-side down in the hot oil. Cook until the fish flesh has turned opaque half way through, then flip the fish and cook skin-side down. Cook time depends on the thickness of the fish. If you have a very thick filet, finish in a 400 degree oven for a few minutes, or return the flame to low and cover the pan for a few minutes. Set fish fillet on a platter or between two plates. Drizzle the top with a spoonful of salsa verde. When the vegetables have finished roasting, toss them together with the remaining salsa. Top the fish with the vegetable mixture and garnish with some chopped chives.