Marinate the chicken by mixing olive oil, garlic powder, onion powder, paprika, salt, and pepper in a bowl. Coat the chicken breasts and let sit for at least 15 minutes.

Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper. Bake the marinated chicken for 25-30 minutes until cooked through.

Rinse the quinoa under cold water. In a saucepan, bring vegetable broth or water to a boil, add quinoa and salt, reduce heat, cover, and simmer for 15 minutes.

Prepare the vegetables by tossing broccoli and bell peppers with olive oil, salt, pepper, and Italian seasoning. Roast in the oven for 20-25 minutes.

Combine mixed greens, cherry tomatoes, and cucumber in a bowl. Drizzle with balsamic vinaigrette just before serving.

Portion the cooked chicken, quinoa, and roasted vegetables into meal prep containers. Keep the salad separate to maintain freshness.