Pat salmon dry and season with salt and pepper. Rest it while making the salsa verde.
Bring a pot of salted water to a boil. Prepare a large bowl of ice water, for blanching. Add chopped greens and stir, letting cook until bright green, about two minutes. Quickly strain from water and submerge in ice water to lock in the color. Strain the greens and set aside.
In another bowl, mix the ¼ cup olive oil, garlic, lemon zest, juice, and capers. Squeeze greens dry and add bowl, stirring in salt and pepper to taste. Let sit at least 10 minutes before serving.
Heat remaining olive oil in a skillet. Once warm (you can test by seeing if a droplet of water sizzles), add salmon, skin side down. Cook for 3-4 minutes, until the flesh starts looking opaque. Flip and cook for 2-3 more minutes, until the full filet is cooked through but still bright pink in the center. The thicker the filet, the longer this will take.
Plate the salmon skin side down and top each filet with a dollop of salsa verde. Serve remaining sauce on the side.
Serve with roasted cauliflower, mixed vegetables, or pasta, either of which can simply be tossed in extra virgin olive oil, salt and pepper and dressed with the same salsa verde.