Lemony caper vinaigrette heightens the flavors of sweet summer corn and crisp, cool cucumber in this unconventional take on salade Nicoise.
Whisk together zest and juice, 7 tablespoons oil, and capers; season with salt and pepper.
In a large pot, cover potatoes with 2 inches of water; season with salt. Bring to a boil and cook until easily pierced with the tip of a knife, 7 to 9 minutes. Transfer to a plate with a slotted spoon. Add beans to pot; boil until crisp-tender, 3 to 4 minutes. Add corn and boil 1 minute more; drain.
Season fish with salt and pepper. Heat a large skillet over medium-high; swirl in remaining 1 tablespoon oil. Add fish, skinside down; cook, flipping once, until skin is crisp and fish is just cooked through, 5 to 6 minutes. Serve, with potatoes, beans, corn, cucumbers, olives, dressing, lemon wedges, salt, and pepper.