01 - Set oven to 425°F and line a large rimmed baking sheet with parchment paper or foil for easy cleanup.
02 - In a small bowl, whisk together olive oil, lemon juice, lemon zest, garlic, oregano, thyme, half of the salt, and half of the black pepper.
03 - Place trimmed green beans and sliced red onion on the prepared baking sheet. Drizzle with half of the marinade and toss to coat evenly. Spread in a single layer, leaving space in the center for the salmon.
04 - Place salmon fillets in the center of the baking sheet. Brush with the remaining marinade. Sprinkle remaining salt and black pepper over the salmon.
05 - Roast in the preheated oven for 16 to 18 minutes, or until salmon flakes easily with a fork and green beans are tender-crisp.
06 - Remove from oven. Garnish with lemon wedges and fresh parsley if desired. Serve immediately.