Preheat the OvenPreheat oven to 400°F (200°C).
Prepare the VegetablesIn a large bowl, toss the Brussels sprouts, carrots, sweet potato, and red onion with olive oil, salt, and pepper until evenly coated.
Roast the VeggiesSpread the vegetables in a single layer on a baking sheet. Roast for 25–30 minutes, stirring once halfway through, until golden and tender.
Assemble the BowlDivide cooked quinoa into bowls. Top with the roasted vegetables and sprinkle with chopped parsley.
Serve and EnjoyServe warm as a main or hearty side dish. Add a squeeze of lemon or a drizzle of tahini if desired.