Preheat the oven to 400°F.
Rinse the quinoa thoroughly and add it to a pot with the water. Bring to a boil, then reduce heat to low and simmer for 15-20 minutes, or until the water is absorbed and the quinoa is tender.
While the quinoa is cooking, chop the mixed vegetables into bite-sized pieces and place them on a baking sheet lined with parchment paper.
Drizzle the vegetables with olive oil and sprinkle with garlic powder, onion powder, salt, and pepper.
Roast the vegetables in the preheated oven for 20-25 minutes, or until they are tender and lightly browned.
In a large mixing bowl, combine the cooked quinoa, roasted vegetables, and chickpeas.
Squeeze the lemon juice over the salad and toss to combine.
Add the chopped parsley and mint, and toss again.