01 - Preheat your oven to 425°F. Line a large sheet pan with parchment paper or foil for easy cleanup.
02 - In a small bowl, whisk together olive oil, lemon juice, garlic, Dijon mustard, honey, oregano, salt, and pepper until well combined.
03 - Place the asparagus and cherry tomatoes on the sheet pan. Drizzle with half of the marinade and toss to coat evenly. Spread vegetables across the pan, leaving space for the salmon.
04 - Nestle the salmon fillets among the vegetables. Brush the tops with the remaining marinade and season with additional salt and pepper.
05 - Scatter the red onion slices over the vegetables and salmon.
06 - Roast in the preheated oven for 15–18 minutes, or until the salmon flakes easily with a fork and the vegetables are tender.
07 - Remove from oven. Garnish with chopped parsley and serve with lemon wedges.