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.
03 - Place the asparagus and cherry tomatoes on the sheet pan. Drizzle with half of the marinade and toss to coat. Spread evenly, 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.
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.