Preheat your oven to 425°F and line a large sheet pan with parchment paper. In a large bowl, combine the zucchini, bell peppers, cherry tomatoes, and red onion. Drizzle with half of the olive oil and season with half of the salt and pepper. Toss to coat evenly and spread the vegetables across the prepared sheet pan, leaving space for the salmon fillets.
In a small bowl, whisk together the remaining olive oil, minced garlic, lemon juice, lemon zest, oregano, and thyme. Season the salmon fillets with the remaining salt and pepper, then brush them generously with the herb oil mixture. Place the salmon fillets on the sheet pan among the vegetables.
Roast for 12-15 minutes, or until the salmon flakes easily with a fork and the vegetables are tender and lightly caramelized. The internal temperature of the salmon should reach 145°F. Remove from the oven and immediately sprinkle with fresh parsley and capers. Serve with lemon wedges and enjoy this heart-healthy Mediterranean feast.