Preheat your oven to 400°F and line a large sheet pan with parchment paper or lightly grease it.
In a small bowl, whisk together maple syrup, soy sauce, 1 tbsp olive oil, minced garlic, Dijon mustard, ginger, and ¼ tsp each of salt and pepper.
Toss the Brussels sprouts, carrots, and red onion with remaining 1 tbsp olive oil, ½ tsp salt, and ¼ tsp pepper. Spread them out on the sheet pan.
Roast the vegetables for 10 minutes while you prepare the salmon.
Remove the pan from the oven and push vegetables to the sides. Place salmon fillets in the center and brush generously with the maple glaze.
Return to the oven and bake for 10-12 minutes, or until salmon is cooked through and flakes easily. Brush with remaining glaze halfway through cooking.
Garnish with fresh thyme or parsley and serve immediately. The glaze should be beautifully caramelized and glossy!